NEW YORK; IN MEMORIAM FLOR1AN CAJORI 2L- s= / 2 J J t '/ 2- s J *) MENTAL ARITHMETIC; OB, ORAL EXERCISES IN ABSTRACT COMMERCIAL ARITHMETIC, WITH FIRST LESSONS IS WRITTEN ARITHMETIC.) FOR TUB USE OF SCHOOLS. BY CHAS. S. TENABLE, / PROFESSOR OP MATHEMATICS IN THE UNIVERSITY OP VIRGINIA*, FORMERLY PROFESSOR OF MATHEMATICS AND ASTRONOMY, UNIVERSITY OF SOUTH CAROLINA; FOR- MERLY PROFESSOR OF NATURAL PHILOSOPHY AND CHEMISTRY, UNI- VERSITY OF GEORGIA; FORMERLY PROFESSOR OF MATHEMA- TICS IN HAMPDEN SIDNEY COLLEGE, VIRGINIA. NEW YORK: RICHARDSON & COMPANY, 14 BOND STREET. 1867. MATHEMATICAL SERIES. 1. First Lessons in Numbers. An illustrated, easy, and attractive Mental Arithmetic, for the use of Families and Primary Schools. Adapted to the OBJECT METHOD. 30 cents. 2. Mental Arithmetic. After the inductive method of Pestalozzi, with first lessons in Written Arithmetic. For Common Schools and Academies. 45 cents. 3. Elements of Written Arithmetic. In which the fundamental operations on Abstract and Denominate Numbers, and their various applications, are thoroughly explained and illustrated by numerous examples adapted to the business of practical life. For the use of Schools. $1.00. 4. High School Arithmetic. FOR THE PSE OF SCHOOLS AND COL- LEGES. In this work the reasoning on the fundamental principles will be more fully developed, and illustrated by a greater variety and number of applications and examples. In addition to the sub- jects usually treated in Text-books of Arithmetic, it will contain several chapters on Notation, Theory of Numbers, Progressions, Logarithms, and the use of Logarithmic Tables. 5. Algebra. FOR THE USE OF SCHOOLS ANI> COLLEGES. Containing the latest improvements. To a thorough discussion of the subjects usually treated in Textbooks on this subject will be added chapters on the Theory of Determinants, and other lessons from the modern higher Algebra, for the use of University Students. 6. Legendre's Geometry* To the complete translation of the latest edition of the standard work of Lespendre will be appended many exercises in Geometrical Analysis, with hints for the solution of the same. Also, notes on the application of the method of Limits to the demonstration of theorems in Elementary Geometry. 7. Analytic Geometry, Part First Plane Co-ordinate Geometry, The Point, Straight Line, Conic Sections, some of the hisrher Plane Curves, Algebraic and Transcendental. Also, the Method of Abridged Notation. Part Second The Point and Straight Line in Space, the Plane, Surfaces of the Second Order, Cones, Cylinders, and Surfaces of Revolution, Conoids, Helicoids, Curves of Double Curvature, Ana- lytical Theory of Projections. RICHARDSON & CO., PUBLISHERS, NEW YORK. Entered according to Act of Congress, in the year 1866, BY RICHARDSOX & CO., In the Clerk's Office of the District Court of the United States for the Southern District of New York. A CONTENTS. CHAPTER I. PAGE Formation of Numbers by Counting Addition Use of the Arabic Figures 7 CHAPTER II. Subtraction 20 CHTAPTER III. Multiplication 30 C3APTER IT. Division 40 CHAPTER V. Miscellaneous Questions 59 CHAPTER VI. Multiples, Divisors, and Prime Factors 67 CHAPTER VII. Fractions Proportion 72 IV CONTENTS. CHAPTER VIII. PAGB Denominate Numbers 119 CHAPTER IX. The Metric System of Weights and Measures 132 CHAPTER X. Percentage Interest 1ST CHAPTER XI. Miscellaneous Problems 151 9 CHAPTER XII. Elementary Lessons in Written Arithmetic 1GO PREFACE. THE advantages of the study of Mental, or Oral, Arithmetic are very generally acknowledged, and yet it is much neglected in the schools. The present work is prepared as a companion to those treatises on written Arithmetic which are not mere collections of examples, but whose aim is to place the study in its proper position among other branches of a rational education. Great care has been taken to arrange the subjects and to select and frame the questions in such a manner that the pupil may not only acquire readiness and accuracy in the solution of numerical problems, but may gain a thorough knowledge of all the simpler relations among numbers, and learn the reason for each step taken in the various operations performed on them. The method pursued is that identified with the name of Pes- talozzi. The clearest exposition of this method in abstract numbers is to be found, perhaps, in Reiner's Lessons in a Pesta- lozzian school in Surrey, England. Use has been made of this, and of Menzel's valuable G-erman collection of examples for " Head-reckoning." The attention of teachers is called to the following points in this little work : Its order and method ; the chapters on mul- tiples, divisors, and prime factors ; the treatment of vulgar frac- tions ; the mode of teaching proportional numbers ; the brief and direct analysis of the various solutions of questions given ; the tables of French decimal weights and measures (now authorized in this country by the United States Government), with appro- priate questions, illustrating the superiority of these tables over tho ordinary ones for ready-reckoning. Yl PREFACE. A few pages of written Arithmetic are appended, for the convenience of those who may wish to acquire some familiarity with the operations' on higher abstract numbers before entering upon the next book of the series. These pages may also be used to advantage concurrently with the rest of the book. SUGGESTIONS TO TEACHERS. 1. Require the pupil to commit to memory the necessary tables of Addition, Subtraction, Multiplication, and Division. 2. Practice the pupil frequently in counting forwards and backwards by twos, threes, tens, &c., &c. This will cause him to understand thoroughly the basis of all the operations on whole numbers, and that Multiplication and Division are abridged forms of Addition and Subtraction. 3. Do not enter upon the subject of fractions until the pupil is very familiar with the questions on factors, multiples, and divisors. 4. Add examples and illustrations to those in the book, and require your pupils in each lesson to frame questions and give their solutions. This will be found a most useful exercise, especially in the miscellaneous questions on Proportion and its applications. 5. Pupils in written Arithmetic should be called on to solve, orally, questions similar to those in each .set of examples which . they work on the slate. MENTAL ARITHMETIC, CHAPTER I. ADDITION. LESSON I. 1. John has one knife ; if his father gives him another, how many will he have ? 2. Frank has two oranges, and Charles one ; how many have they both together ? 3. James is in school three hours every morning, and one hour each evening ; how many hours is he in school each day ? 4. A boy took four eggs from one bird's nest, and one from another ; how many birds' eggs did he take ? 5. Mary has five tulips in bloom on one bed in the farden, and one upon another ; how many tulips loom on both beds ? 6. One and one are How many ? Two and one ? Three and one ? Four and one ? Five and one ? Six and one? Seven and one ^ Eight and one? Nine and one ? Ten and one ? 7. Count from one to ten. Count the birds you know. Count the flowers you know. Count from ten to twenty. Count the number of words in the first two questions of this lesson. Count from twenty to thirty. Count from thirty to forty. 8. Begin at twenty and add successively the letters of the sentence, " Labor overcomes the greatest diffi- 8 ADDITION. culties." Count from fifty to sixty. From sixty to seventy, eighty, ninety, one hundred. Commence at the first word of this lesson, and count the words as far as one hundred. 9. How many tens have you counted in counting twenty ? in counting thirty ? forty ? fifty ? sixty ? seventy ? eighty ? ninety ? one hundred ? 10. Count from one hundred to two hundred. 11. How would you count from two hundred to three hundred ? ANS. By counting from one to one hundred^ and repeating two hundred before each number counted. 12. How would you count from three hundred to four hundred ? to five hundred ? six hundred ? seven hundred? eight hundred? nine hundred? ten hun- dred? 13. What do we call ten hundred ? ANS. One thousand. LESSON II. 1. A man has fifty-two white sheep and one black one; how many has he altogether? 2. One company of soldiers has sixty-five men in it, a second company has one man more ; how many men in the second company ? 3. Of a flock of blackbirds, forty-five are on a tree, and one on the fence : how many blackbirds in the flock? 4. Ten and one are how many? Twenty and one ? Thirty and one ? Forty and one ? Fifty and one ? Seventy and one ? Ninety and one ? 5. Eleven and one are how many ? Twenty-one and one ? Thirty-one and one ? Fifty-one and one ? Sixty-one and one ? Eighty -one and one ? One hun- dred and one and one ? 6. Twelve and one are how many ? Twenty-two ADDITION. 9 and one ? Thirty-two and one ? Forty-two and one ? Fifty-two and one? Sixty-two and one? Seventy- two and one ? Eighty -two and one ? Ninety-two and one ? 7. Fourteen and one? Twenty-four and one? Thirty- four and one ? Forty-four and one ? Fifty-four and one? Sixty-four and one ? Seventy-four and one ? Eighty-four and one ? Ninety-four and one ? 8. Fifteen and one are how many ? Twenty-five alid one ? &c. 9. Nineteen and one are how many ? Twenty-nine and one? &c. 10. One ten and one ten are how many ? Two tens and one ten ? Three tens and one ten ? Seven tens and one ten? Eight tens and one ten? Ten tens and one ten ? 11. One hundred and one hundred are how many? Two hundred and one hundred ? Three hundred and one hundred? Four hundred and one hundred? Nine hundred and one hundred ? LESSON III. 1. Two oranges and two oranges are how many oranges ? 2. A planter made three bales of cotton on one acre of land, and two on another acre ; how many bales did he make on both ? . 3. Charles has three marbles, and James has three ; how many have they together ? 4. A traveller walked three miles the first hour, and four miles the second ; how many miles did he walk in the two hours ? 5. A planter makes five hogsheads of tobacco one year, and four the next ; how many hogsheads in the two years ? i* 10 ADDITION. 6. One and two are how many ? One and three ? One and four ? 7. Two and two ? Two and three ? Two and four ? 8. Three and two? Three and three? Three and four? 9. Four and two ? Four and three ? Four and four? 10. Five and two ? Five and three ? Five and four? 11. Six and two? Six and three? Six and four? 12. Seven and two ? Seven and three ? Seven and four? 13. Eight and two ? Eight and three ? Eight and four ? 14. Nine and two ? Nine and three ? Nine and four ? 15. Ten and two ? Ten and three ? Ten and four ? 16. Twenty and two are how many ? Thirty and two? Forty and two? Fifty and two? Sixty and two ? Seventy and two ? Eighty and two ? Ninety and two ? 17. Twenty and three are how many ? &c. 18. Twenty and four are how many? &c. The teacher will cause the pupil to go through the same addition as above with three and four. i 19. Eleven and two are how many? Twenty-one and two ? Thirty-one and two ? Forty-one and two ? Fifty-one and two ? Sixty-one and two ? Seventy- one and two ? Eighty-one and two ? Ninety-one and two? 20. Eleven and three are how many ? Twenty -one and three ? &c. 21. Eleven and four are how many? Twenty-one and four? &c. 22. Twelve and two are how many ? .Twenty-two and two ? &c. ADDITION. 11 23. Twelve and three are how many ? Twenty-two and three ? &c. 24. Twelve and four are how many ? Twenty -two and four ? &c. 25. Thirteen and two ? Twenty-three and two ? &c. 26. Thirteen and three ? Twenty -three and three? &c. 27. Thirteen and four? . Twenty-three and four? &c. 28. Fourteen and two ? Twenty-four and two ? &c. 29. Fifteen and two ? Twenty-five and two ? &c. 30. Sixteen and two ? Twenty-six and two ? &c. 31. Seventeen and two ? Twenty-six and two ? &c. 32. Eighteen and two ? Twenty-eight and two ? &c. 33. Nineteen and two ? Twenty-nine and two ? &c. The teacher should extend these questions as far as ninety-three in, the same manner with those which are completed, and make the same series of additions with three and four. 34. Count by twos to one hundred and one, begin- ning with one. 35. Count by twos to one hundred, beginning with two. 36. Count by threes to one hundred, -beginning with one. 37. Count by threes to one hundred and one, begin- ning with two. 38. Count by threes to ninety-nine, beginning with three. 39. Eighty-seven and one, and two, and three, are how many ? 40. Ninety two and two, and three, and four, are ow many? 41. Thirty-five and two, and three? Forty-three ,nd four, and two? Fifty-four and four, and three ? 12 ADDITION. LESSON IV. We have thus far written out the names of the different numbers. For the sake of abbreviation in the succeeding lessons, we will use the figures of the Arabic notation. These are one two three four five six seven eight nine zero or naught 1234567 89 NOTE. For a more detailed explanation of the use of figures, see first lessons in Numbers, page 31. We have seen, in counting, there are two tens in twenty, three in thirty, four in forty, &c., and ten tens in one hundred. If now we wish to express numbers greater than nine by those figures, we may do so readily by the use of columns and the (zero). ADDITION. 13 Hundreds. Tens. Units or ones. 5 6 4 123 100 Thus 5 in the column of tens and 6 in the column of ones or units, means five tens and six units, or fifty- six ; 4 in the column of tens and in the column of units indicates four tens and no units, of forty ; 1 in the column of hundreds, and 2 in the column of tens, and 3 in that of units, indicates one hundred, two tens, and three units, or one hundred and twenty-three ; 1 in the hundreds column, in tens, and in units, indi- cates one hundred. We leave out the columns in the actual writing of numbers and write them thus : 56, 40, 123, 100, and simply recollect the local values of the figures. 1. What is the local value of r the figure on the right of a number ? ANS. Units. 2. What is the local value of the figure next to the right-hand figure ? 3. The third figure from the right ? the fourth ? 4. What is the meaning and use of the 0? NOTE. The pupil should now be required to read the following table, and be drilled in the use of figures, until he can readily write any number from one to one thousand in figures: 10 20 40 30 88 11 21 41 31 90 12 22 42 32 93 13 23 43 60 99 14 24 44 61 100 15 25 45 62 110 16 26 50 70 101 17 27 51 78 255 18 28 52 80 999 19 29 53 81 1000 14 ADDITION. LESSON V. 1. John bought a lemon for five cents, and an apple for five cents ; how much did they both cost him ? 2. One man rides six miles in one hour, and another rides three miles more than the first ; how many miles does the latter ride in one hour? 3. Edward begins to work at six o'clock in the morning and works five hours ; at what o'clock does he stop, work ? 4. Harry has seven peaches, and Frank has five ; how many peaches have both ? 5. A farmer has seven cows in one pasture, and nine in another ; how many has he in both ? 1 and 7 \ 6. 7. 8. 9. 10. 11. 12. 13. 14. 1 2 3 4 5 6 7 8 9 and and and and and and and and and 5 are how 5 ? 2 and 5 ? 3 and 5 ? 4 and 5 ? 5 and 5 ? 6 and 53 7 and 5 ? 8 and 5 ? 9 and many \ 6? 2 6? 3 6? 4 6? 5 6? 6 6? 7 6? 8 6? 9 1 and and and and and and and and and 6? 7? 7? 7? 7? 7? 7? 7.1 7? 15. 10 and 5 are how many ? 20 and 5 ? 30 and 5 ? 40 and 5 ? 50 and 5 ? 60 and 5 ? 70 and 5 2 80 and 53 90 and 5 ? 16. 10 and 6 are how many ? 20 and 6 ? &c. 17. 10 and 7 are how many ? 20 and 7 ? &c. 18. 11 and 5 are how many ? 21 and 5 ? &c. 19. 11 and 6 are how many ? 21 and 6 ? &c. 20. 11 and 7 are how many ? 21 and 7 ? &c. , 21. 12 and 5 are how many ? 22 and 5 ? &c. 22. 12 and 6 are how many ? 22 and 6 ? &c. . 23. 12 and 7 are how many ? 22 and 7 ? &c. 24. 13 and 5 are how many ? 23 and 5 ? &c. 25. 13 and 6 are how many ? 23 and 6 ? &c. ADDITION. 15 26. 13 and 7 are how many ? 23 and 7 ? &c. 27. 14 and 5 are how many ? 24 and 5 ? &c. 28. 14 and 6 are how many ? 24 and 6 ? &c. 29. 14 and 7 are how many ? 24 and 7 ? &c. 30. 15 and 5 are how many ? 25 and 5 ? &c. 31. 16 and 5 are how many ? 26 and 5 ? &c. 32. 17 and 5 are how many ? 27 and 5 ? &c. 33. 18 and 5 are how many ? 28 and 5 ? &c. 34. 19 and 5 are how many ? 29 and 5 ? &c. To be carried out as far as 91, 92, 93, 94, &c., by the pupil, for 5, 6, and 7. LESSON VI C I. 1 Count by 5's to 101, beginning with 1. To 102, beginning with 2. To 103, beginning with 3. To 104, beginning with 4. To 100, beginning with 5. 2. Count by 6's, beginning with 1, 2, 3, 4, 5, 6, re- spectively. Thus, 1, 7, 13, &c. 2, 8, 14, &c., &c. 3. Count by 7's, beginning with 1, 2, 3, 4, 5, 6, re- spectively. Thus, 1, 8, 15, &c. 2, 9, 16, &c., &c. 4. A man had sixty-five sheep in one fold, five in a second, six in a third, and seven in a fourth ; how many had he altogether ? 5. A farmer gathered fifty-six barrels of apples from his orchard, and seven barrels from two trees which stood in the corner of his yard ; how many bar- rels did he gather ? 6. There are three hundred soldiers in one regi- ment, and six hundred in another ; how many in the two regiments? 7. 2 tens and 5 tens are how many ? 2 tens and 6 tens ? 2 tens and 7 tens ? 8. 9 tens and 5 tens are how many ? 9 tens and 6 tens ? 9 tens and 7 tens ? 9. 3 hundred and 5 hundred are how many ? 3 hundred and 6 hundred ? 3 hundred and 7 hundred ? 16 ADDITION. 10. 4 hundred and 5 hundred are how many ? 4 hundred and 6 hundred ? 4 hundred and 7 hundred ? 11. Add fifty-seven, seven, six, and five. 12. Add forty-nine, seven, five, three, and four. 13. How many are ninety-seven, six, seYen, four, seven, and three? 14. How many are forty-five, six, three, five, six, four, three, and four ? LESSON VII. 1. Frank is seven years old, his sister is eight years older ; how old is his sister ? 2. Thomas killed six squirrels on Monday, and nine on Tuesday ; how many squirrels did he kill on both days? 3. A gardener gathered five bushels of apples from one tree, and ten bushels from another ; how many bushels from the two trees ? 4. 1 and 8 are how many ? 1 and 9 ? 1 and 10 ? 5. 2 and 8 ? 2 and 9 ? "2 and 10 ? 6. 3 and 8? 3 and 9 ? 3 and 10? 7. 4 and 8 ? 4 and 9 ? 4 and 10? 8. 5 and 8 ? 5 and 9 ? 5 and 10 ? 9. 6 and 8 ? 6 and 9 ? 6 and 10 ? 10. 7 and 8? 7 and 9? 7 and 10? 11. 8 and 8 ? 8 and 9 ? 8 and 10 ? 12. 9 and 8? 9 and 9 ? 9 and 10 ? 13. 10 and 8 are how many ? 20 and 8 ? 30 and 8 ? &c., to 98. 14. 11 and 9 are how many ? 21 and 9 ? 81 and 9 ? &c., to 10. 15. 12 and 10 are how many ? 22 and 10 ? 32 and 10 ? &c., to 102. 16. 13 and 8 are how many ? 23 and 8 ? 33 and 8 ? &c., to 101. 17. 14 and 9 are how many ? 24 and 9 ? 34 and 9 ? &c., to 103. ADDITION. IT 18. 15 and 10 are how many? 25 and 10 ? 35 and 10 ? &c., to 105. 19. 1 6 and 8 are how many ? 26 and 8 ? 36 and 8? &c., to 104. 20. 17 and 9 are how many ? 27 and 9 ? 37 and 9 ? &c., to 106. 21. 18 and 10 are how many ? 28 and 10 ? 38 and 10 I &c., to 108. 22. 19 and 8 are how many ? 29 and 8 ? 39 and 8 ? &c., to 107. 23. 10 and 10 are how many ? 20 and 10 ? 30 and 10? &c., to 100. 24. How much is forty-five and eight ? , Two and seven and five and eight and nine are how many ? 25. Fifty-seven and eight are how many ? 26. Ninety-three and nine ? one hundred and sixteen and ten ? 5, 9, 6, 9, 3, 8, 7, 2, and 1 are how many? Ninety-seven, eight, nine, and ten are how many ? LESSON VIII. 1. Count by 8's, beginning with 1, 2, 3, 4, 5^6, 7, and 8 respectively. Thus, 1, 9, 17, &c. 2, 10. 18, &c., &c. 2. Count by 9's, beginning with 1, 2, 3, 4, 5, 6, 7, 8, and 9 respectively. Thus, 1, 10, 19, &c. 2, 11, 20, &c., &c. 3. Count by 10's, beginning with 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 respectively. Thus, 1, 11, 21, &c. 2, 12, 22, &c., &c. 4. A farmer sends sheep to market in two droves, one drove has twenty sheep in it and the other eighty ; how many sheep in both droves ? 5. A man makes five hundred bushels of wheat on one farm, and nine hundred on another ; how many hundred bushels does he make on both farms? 6. A grazier has one hundred and seventeen head of 18 ADDITION. cattle in one field, and ten head in another ; how many head in the two fields ? 7. 3 tens and 8 tens are how many tens ? 3 tens and 9 tens ? 3 tens and 10 tens ? 8. 8 tens and 8 tens are how many tens ? 8 tens and 9 tens? 8 tens and 10 tens ? 9. 2 hundred and 8 hundred are how many hun- dred ? 2 hundred and 9 hundred ? 2 hundred and 10 hundred ? 10. 7 hundred and 8 hundred ? 7 hundred and 9 hundred ? 7 hundred and 10 hundred \ LESSON IX. 1. A father has three books, and wishes to give them to his three sons ; how many would he give to each son? 2. If he wished to give them to two sons, how many would he give to one and how many to the other? 3. Three can be broken up how ? ANS. Into three ones, or into two and one. 4. 4: can be separated into what numbers ? ANS. 3 and 1, 2 and 2, 1 and 1 and 1 and 1. 5. What different numbers added together make 5? 6. A boy has six marbles ; into what different heaps can he distribute them ? 7. 6 can be separated into what numbers ? 8. 7 can be separated into what numbers ? 9. What different numbers added together will makeS? 9? 10? When a number is greater than ten, and less than one hundred, the inost usual and useful separation in our system of numbers is into tens and units ; or, if greater than one hundred, and less than a thou- sand, into hundreds, tens, and units. The notation or mode of writing numbers, which has been explained in a previous lesson, makes this separation very easv. 18 ADDITION. 1 9 10. Separate 11, 12, 13, 14, 15, 27, 49, 58, and 97 into tens and units. 11. Separate 137, 142, 156, 207, 320, 197 into hun- dreds, tens, and units, and into tens and units. 12. 25 and 19 are how many? PROCESS. Separate 19, and we have 1 ten and 9 units ; 25 and 10 are 35 ; 35 and 9 are 44. Hence, 25 and 19 are 44. 13. 34 and 14 are how many ? 31 and 18 ? 32 and 17 ? 32 and 16 ? 14. 14 and 19 ? 95 more 13 ? 46 and 12 ? 15. 11 and 11 are how many ? 22 and 11 ? 33 and 11? 16. Count by ll's to 99, beginning with 11. 17. 12 and 12 are how many ? 24 and 12 ? 36 and 12? 18. Count by 12's to 96, beginning with 12. 19. 40 and 20 are how many ? 50 and 30 ? 60 and 40 ? 30 and 60 ? 70 and 20 ? 90 and 50 ? 20. 40 and 27 are how many ? PROCESS. 27 ^ 20 andl; 40 and 20 are 60, 60 and 7 make 67. 21. How much is 60 and 32? 70 and 29? 90 and 67 ? 50 and 48 ? 80 and 22 ? 22. 47 and 20 are how many? 58 and 30? 65 and 40 ? 33 and 30 ? 72 and 20 ? 23. 48 arid 27 are how many ? PROCESS. 40 and 20 are 60; 8 and 7 are 15; 60 and 15 are 75. Or thus, 27 is 20 and 7, 48 and 20 make 68, 68 and 7 make 75. 24. 72 and 25 are how many ! 64 and 56 ? 31 and 22 ? 48 and 63 ? 84 and 26? 20 SUBTRACTION. CHAPTEE II. SUB TRACTION. LESSON I. 1. A boy has one apple, and gives it away ; how many has he left ? Another has twenty apples and gives them away ; how many has he left ? 2. 1 from 1 leaves how many ? 20 from 20 leaves how many ? 3. Any number taken from itself leaves what ? 4. A boy has five peaches, and eats one of them ; how many has he left ? 5. Mary had five books, but she has lost two of them ; how many has she now? 6. "William had ten canary birds in a cage, but al- lowed two of them to escape ; how many has he left ? 7. What do you call the result obtained by adding one number to another ? ANS. Their sum. 8. What do you call the result obtained by taking one number from another ? ANS . Their differ en ce. 9. 1 from 1 leaves how much ? 2 less 2 is ? 10. 1 from 2 leaves ? 3 less 2 ? 11. 1 from 3 leaves? 4 less 2 ? 12. 1 from 4 leaves? 5 less 2 ? 13. 1 from 5 leaves ? 6 less 2 ? 14. 1 from 6 leaves ? 7 less 2 ? 15. 1 from 7 leaves ? 8 less 2 ? 16. 1 from 8 leaves ? .9 less 2 ? 17. 1 from 9 leaves? 10 less 2 ? 18. 1 from 10 leaves ? 19. 11 less 1 is ? 21 less 1 ? 31 less 1 ? 41 less 1 ? 51 less 1? 61 less 1? 71 less 1? 81 lessl? 91 less 1? SUBTRACTION. 21 20. 11 less 2 ? 21 less 2 ? &c., to 101. 21. 22 less 1 ? 23 less 1 ? 24 less 1 ? 35 less 1 ? 46 less 1 ? 22. 57 less one? 68 less 1? 79 less 1 ? 110 less 1 ? 23. 12 less 2 is how much? 22 less 2? &c., to 102. 24. 13 less 2 ? 23 less 2 ? &c., to 103. 25. 14 less 2 ? 24 less 2 ? &c., to 94. 26. 15 less 2 ? 25 less 2 ? &c., to 95. 27. 16 less 2 ? 26 less 2 ? &c., to 96. 28. 18 less 2? 28 less 2? &c., to 98. 29. 19 less 2? 29 less 2? &c., to 99. 30. Begin at 100, and count backward down to 1. 31. Begin with 100, and count backwards by 2's down to 2. 32. Begin with 99, and count backwards by 2's down to 1. 33. 1 ten from 2 tens leaves how many? 1 ten from 3 tens? 34. 1 ten from 6 tens ? 2 tens from 8 tens ? 35. 1 hundred from 4 hundred leaves how many ? 1 hundred from 8 hundred ? 2 hundred from. 7 hun- dred I 2 hundred from 9 hundred 3 LESSON II. 1. George had ten chickens, but y a weasel killed three of them ; how many remained ? 2. One farmer has seven horses and another has four ; how many more has the first than the second ? 3. A man planted twelve trees, but five of them died ; how many lived ? 4. A man owing thirteen dollars, paid three of them ; how much did he still owe ? 5. A farmer had fifteen cows in one pasture, and five in a second ; how many more were in the first pas- ture than in the second 'I SUBTRACTION. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 3 less 4 less 5 less 6 less 7 less 8 less 9 less 10 less 11 less 12 less 3 3? 3? 3? 3? 3? 3? 3? 3? 3? 4 5 6 7 8 9 10 11 12 13 less less less less less less less less less less 4? 4? 4? 4? 4? 4? 4? 4? 4? 4? 5 less 5 ? 6 less 5 ? 7 less 5 ? 8 less 5 ? 9 less 5 ? 10 less 5 ? 11 less 5 ? 12 less 5 ? 13 less 5 ? 14 less 5 ? 16. 13 less 3? 14 less 4? 15 less 5 ? 17. 10 less 3? 20 less 3? 30 less 3? &c., to 90. 18. 11 less 3? 21 less 3? 31 less 3? &c., to 91. 19. 12 less 3? 22 less 3? 32 less 3? &c., to 92. 20. 13 less 3? 23 less 3? 33 less 3? &c., to 93. 21. 14 less 3? 24 less 3? 34 less 3? &c., to 94. 22. 15 less 3? 25 less 3? 35 less 3? &c., to 95. 23. 16 less 3? 26 less 3? 36 less 3? &c., to 96. 24. 17 less 3? 27 less 3? 37 less 3? &c., to 97. 25. 18 less 3? 28 less 3? 38 less 3? &c., to 98. 26. 19 less 3? 29 less 3? 39 less 3? &c., to 99. NOTE. The teacher should cause the pupil to go through several of the above subtractions with 4 and 5 respectively. 27. Count by 3's backwards from 100 to 1. 28. Count by 4's backwards from 100 to 0. 29. Count by 5 's backwards from 100 to 0. 30. 3 tens from 8 tens leaves how many ? 4 tens from 7 tens ? 5 tens from 9 tens ? 31. One veteran regiment has 400 men in it, and another 500 men ; how many more in the last than in the first ? 32. 3 hundred from 6 hundred leaves how many ? 7 hundred less 5 hundred is ? 33. 4 hundred from 8 hundred leaves how many? 6 hundred from 9 hundred ? 2 hundred from 7 hundred ? SUBTRACTION. 23 LESSON III. 1. A horse travelled six miles in one hour, and nine miles the next ; how many more miles did he travel in the second hour than in the first ? 2. A farmer paid twelve dollars to one laborer, and i eight dollars to another; how much less did he pay the second laborer than the first ? 3. Julian found thirteen eggs, and gave John seven ; how many had he left? 4. A hunter killed ten bears in the canebrake one day, and six on the next day; how many more did he kill on the first day than the second ? 5. 6 less 6 7 less 7 ? 8 less 8 ? 6. 7 less 6 ? 8 less 7 3 9 less 8 ? 7. 8 less 6 \ 9 less 7 \ 10 less 8 ? 8. 9 less 6 \ 10 less 7 \ 11 less 8 ? 9. 10 less 6 ? 11 less 7 ? 12 less 8 1 10. 11 less 6 ? 12 less 7 ? 13 less 8 ? 11. 12 less 6 \ 13 less 7 ? 14 less 8 1 12. 13 less 6 ? .14 less 7 ? 15 less 8 ? 13. 14 less 6 ? 15 less 7 ? 16 less 8 ? 14. 15 less 6 ? 16 less 7 2 17 less 8 2 15. 16 less 6 ? 17 less 7 ? 18 less 8 ? 16. 20 less 7 is how much ? 30 less 7 ? &c., to 90. 17. 21 less 7 is how much ? 31 less 7? &c., to 91. 18. 22 less 7 ? 32 less 7 ? &c., to 92. 19. 23 less 7 ? 33 less 7 ? &c., to 93. 20. 24 less 7 ? 34 less 7 ? &c., to 94. 21. 25 less 7 2 35 less 7 ? &c., to 95. 22. 26 less 7 ? 36 less 7 ? &c., to 96. 23. 27 less' 7 ? 37 less 7 ? &c., to 97. 24. 28 less 7 ? 38 less 7 ? &c., to 98. 25. 29 less 7 ? 39 less 7 ? &c., to 99. NOTE. The pupil should be required to go through several of the above with 6 and 8 respectively. 26. Count by 6's backward from 100 to 4. 24 SUBTRACTION. 27. Count by 7's backwards from 100 to 2. 28. Count by 8's backwards from 100 to 4. 29. A man has 60 sheep in one fold, and 90 in a second fold ; how many more in the second than in the first ? 30. 6 tens from 9 tens leaves how many ? 7 tens from 10 tens leaves ? 8 tens from 12 tens ? 31. There were 700 bison in one herd on the prairie, and 900 in another herd ; how many more in the last herd than the first ? ' 32. 600 from 900 leaves how many ? 8 hundred from 11 hundred ? LESSON IV. 1. A man agreed to labor for a farmer 15 days, and left at the end of nine days ; how many days' labor did he still owe the farmer ? 2. A hunter on the Texas prairies killed 10 deer on one day, and 14 the next ; how many more did he kill on the second day than on the first ? 3. 9 less 9 are how many ? 10 less 10 are how many ? 4. 10 less 9? 11 less 10? 5. 11 less 9 ? 12 less 10 ? 6. 12 less 9 ? 13 less 10 ? 7. 13 less 9? 14 less 10? 8. 14 less 9? 15 less 10? 9. 15 less 9 ? 16 less 10 ? 10. 16 less 9 ? 17 less 10 ? 11. 17 less 9? 18 less 10? 12. 18 less 9 ? 19 less 10 ? 13. 19 less 9? 20 less 10? 14. 20 less 9 are how many ? 30 less 9 ? &c., to 90. 15. 21 less 9 ? 31 less 9 ? &c., to 91. 16. 22 less 9 ? 32 less 9 ? &c., to 92. 17. 23 less 9 ? 33 less 9 ? &c., to 93. SUBTRACTION. 25 18. 24 less 9 ? 34 less 9 ? &c., to 94. 19. 25 less 9 ? 35 less 9 ? &c., to 95. 20. 26 less 9 ? 36 less 9 ? &c., to 96. 21. 27 less 9 ? 37 less 9 ? &c., to 97. 22. 28 less 9 ? 38 less 9 ? &c., to 98. 23. 29 less 9 ? 39 less 9 ? &c., to 99. NOTE. The pupil should go through in the same manner with the subtraction of 10. 24. Count backwards by 9's from 100 to 1. 25. Count backwards by 10's from 100 to 0. 26. One squadron of cavalry contains 90 mounted men, and a second contains 110; how many more mounted men does the second contain than the first ? 9 tens from 11 tens leaves how many? 10 tens from 15 tens leaves how many ? 27. In one of the butcheries in Paris, 9 hundred sheep were slaughtered in one day, and in a second 12 hundred; how many more were slaughtered in the second than in the first ? 28. 10 hundred or a thousand from 14 hundred leaves how many ? LESSON Y. 1. How much is 20 less 11 ? PROCESS. 11 is 10 and I. 10 from 20 leaves 10, and \from 10 leaves 9. 2. How much is 45 less 11 ? 67 less 11 ? 99 less 11 ? 88 less 11 ? 66 less 11 ? 3. How much is 25 less 12 ? PROCESS. 12 is 10 and 2. 10 from 25 leaves 15, \ind 2 from 15 leaves 13. 4. How much is 43 less 12 ? 54 less 12 ? 60 less 12 ? 72 less 12 ? 96 less 12 ? 84 less 12? . 5. 26 less 13? 52 less 13? 39 less 13? 65 less 13? 26 SUBTRACTION. 6. 28 less 14 ? 42 less 14 ? 70 less 14 ? 7. 36 less 18 ? 54 less 18 ? 90 less 18 ? 8. Count backwards by ll's, beginning with 99. 9. Count backwards by 12's, beginning with 96. 10. How much is 30 less 20 ? 40 less 20 ? 50 less 30? 60 less 20? 70 less 50 ? 80 less 60 ? 90 less 30? 11. How much is 40 less 25 ? PROCESS. 25 is 20 and 5. 40 less 20 is 20. 20 less 5 is 15. 12. How much is 30 less 22 ? 50 less 36 ? 60 less 37 ? 70 less 24 ? 80 less 48 ? 90 less 55 ? 13. How much is 55 less 20 ? PROCESS. 50 less 20 is 30. Hence 55 less 20 is 35. 14. How much is 36 less 20 ? 48 less 20 ? 59 less 30 2 67 less 40 ? 77 less 50 ? 87 less 30 ? 15. How much is 33 less 23 ? 66 less 46 ? 56 less 36? 87 less 67? 97 less 57? 79 less 49? 88 less 28? 16. How much is 55 less 22 ? PROCESS. 55 is 52 and 3. 52 less 22 is 30. 30 and 3 are 33. Or thus, 22 is 20 air of spurs will make eight spurs ? 42 DIVISION. 13. How many pair of spectacles require ten glasses ? 14. An ivory hunter gets two tusks from each ele- phant which he kills ; how many elephants must he kill to get 12 tusks ? 15. If Frank studies two hours *a day, in how many days will he study 14 hours ? 16. How many 2's in 4? 6? 8? 10? 12? 14? 16? 18? 20? 17. In what number is 2 contained exactly 2 times ? 3 times ? 4 times ? 5 times ? 6 times ? 7 times ? 8 'times ? 9 times ? 10 times ? 18. How much is 2 divided by 2 ? 12 divided by 2 ? 4 divided by 2 ? 14 divided by 2 ? 6 divided by 2 ? 16 divided by 2 ? 8 divided by 2 ? 18 divided by 2 ? 10 divided by 2 ? 20 divided by 2 ? The numbers which contain 2 an exact number of times we say are divisible by 2. 19. How many pair of spurs will five spurs make ? 20. If we endeavor to distribute 5 into 2's what do we find ? 7 into 2's ? 9 into 2's ? 21. "What is the 1 which is left in each case called ? ANS. The remainder. 22. How much is 3 divided by 2 ? ANS. 1 and 1 remainder. 23. How much is 5 divided by 2 ? 13 divided by 2 ? 7 divided by 2 ? 15 divided by 2 ? 9 divided by 2 ? 17 divided by 2 ? 11 divided by 2 ? 19 divided by 2 ? 24. "What are the numbers called which are divisible by 2? ANS. Even numbers. 25. What are the numbers called which are not divisible by 2 ? ANS. Odd numbers. 26. What remainder results always when we divide the odd numbers by two ? DIVISION. 43 27. Give the even numbers from 2 to 100. 28. Give the odd numbers from 1 to 99. 29. How much is 4 tens or 40 divided by 2 ? ANS. 2 tens or 20. 30. 4 hundred divided by 2 ? 31. 6 tens or 60 divided by 2 ? 32. 6 hundred divided by 2 ? 33. 8 tens or 80 divided by two? 8 hundred divided by 2 ? 34. 10 tens or 100 divided by 2 ? 10 hundred divided by 2 ? 35. 12 tens or 120 divided by 2 ? 14 tens divided by 2 ? 16 tens divided by 2 ? 18 tens divided by 2 ? 36. How much is 30 divided by 2 ? PROCESS. 30 is 20 -f 10. 20 divided ly 2 is 10, and 10 divided l)y 2 is 5. ANS. 10 + 5 or 15. 37. How much is 50 divided by 2 ? 70 divided by 2? 90 divided by 2? 38. How much is 21 divided by 2 ? PROCESS. 21 is 20 + 1. Hence, 21 divided ~by 2 t's 10 and 1 remainder. 39. How much is 23 divided by 2 ? 24 ? 25 ? 36 ? 45? 40. If we multiply 5 by 2, and divide the product by 2, what will be the quotient ? 41. If we divide 8 by 2, and multiply the quotient by 2, what will be the product ? 42. If we divide any number by 2, and multiply the quotient by 2, what will be the result ? LESION II. *1. If one flour barrel holds 3 bushels, how many barrels will hold 9 Bushels ? 12 bushels ? 15 bushels ? 30 bushels ? 2. Into how many ranks of four men eaeh can you 44 DIVISION. divide a squad of 8 soldiers ? a squad of 16 soldiers ? a company of 30 soldiers ? of 40 soldiers ? 3. Into how many heaps of five balls each can you 15? 18? 21? distribute 25 cannon balls ? 30 cannon balls ? " 45 cannon balls ? 50 cannon balls ? 4. How many 3's in 6 ? 9 ? 12 ? 24? 27? 30? many 4's in 8 ? 12? 16? 20? 24? 36 ? 40 ? many 5's in 10? 15? 25? 20? 30? 40?' 50? 5. 28? 6. 35? 7. In Twice ? times ? 8. In Once ? 5 times? How 32? How 45? what number is 3 contained exactly once? 6 times? 4 times ? 7 times ? 5 times ? 9 8 times ? 10 times ? 3 times ? what number is 4 contained exactly twice ? 4 times ? 8 times ? 10 times ? 6 times ? 7 times ? 3 times ? 9 times ? 9. In what number is 5 contained exactly 4 times? Twice ? 6 times ? 5 times ? 3 times ? 7 times ? 9 times ? 8 times ? 10 times ? 3 divided by 3 ? 6 divided by 3 ? 9 divided by 3 ? 12 divided by 3 ? 15 divided by 3 ? 18 divided by 3 ? 21 divided by 3? 24 divided by 3 ? 27 divided by 3 ? 30 divided by 3 ? 11. How much is 3 x many times ? 3 in 36 ? 12. How much is 4 x many times ? 4 in 48 ? 13. How much is 5 x many times ? 5 in 60 ? 10. How much is 4 divided by 4 ? 8 divided by 4 ? 12 divided by 4 ? 16 divided by 4? 20 divided by 4 ? 24 divided by 4 ? 28 divided by 4? 32 divided by 4 ? 36 divided by 4? 40 divided by 4 ? 11? 3 x 5 divided by 5 ? 10 divided by 5 ? 15 divided by 5? 20 divided by 5 ? 25 divided by 5 ? 30 divided by 5? 35 divided by 5 ? 40 divided by 5 ? 45 divided by 5 ! 50 divided by 5 ? 12? 3 in 33 how 11? m 4 x 12? 4 in 44 how 11 ? 5x12? 5 in 55 how DIVISION. 45 14. 3 is contained in 4 how many times, and what remainder ? in 5 how many times ? 15. How many three bushel bags can you fill with 7 bushels of wheat, and what will remain? How many with 8- bushels? 16. What are the remainders of numbers divided by 3? 17. Give the numbers from 1 to 100 which are divisible by 3. 18. 4 in 5 how many times ? 4 in 6? 4 in 7? 4 in 9 ? 4 in 10 ? 4 in 11 ? What are the remainder of numbers divided by 4 ? 19. Give the numbers from 1 to 100 which are divisible by 4. 20. 5 in 6 how many times ? 5 in 7 ? 5 in 8 ? 5 in 9? 5 in 11? 5 in 12? 5 in 13? 5 in 14? What are the remainders of numbers divided by 5 ? 21. Give the numbers from 1 to 100 which are divisible by 5. 22. 3 in 3 tens how many times ? in 6 tens ? in 9 tens? in 12 tens? &c. 23. 3 in 3 hundred how many times ? in 6 hun- dred? in 9 hundred? in 12 hundred ? 24. 4 in 4 tens? in 8 tens? in 16 tens? in 24 tens? 25. 4 in 4 hundred? in 8 hundred? in 16 hun- dred? 26. 5 in 5 tens? 10 tens? 15 tens? in 5 hun- dred? 15 hundred? 27. Multiply 9 by 3, 4 and 5, and divide the pro- ducts by 3, 4 and 5 respectively. 28. Divide 60 by 3, 4 and 5, and multiply the quo- tients bv 3, 4 and 5 respectively. 29. A number multiplied by 3 and the product divided by 3 gives what result? DIVISION. LESSON III. 1. If it requires 6 horses to draw each cannon on the field of battle, how many cannon will require 12 horses? 24 horses? 42 horses? 36 ' horses ? 60 horses ? 2. How many weeks do 14 days make ? 28 days ? 21 days? 35* days? 49 days? 56 days? 70 days? 3. If 8 leaves only are left to grow and ripen on each tobacco plant, how many plants will yield 16 leaves? 32 leaves? 48 leaves? 40 leaves? 80 leaves ? 4. How 42? 54? 5. 42? many 6's in 12 ? 24 ? 18 ? 36 ? 48 ? 60? 30? many 7's in 14? 28? 21? 35? 49? 63 ? 70 ? many 8's in 16 ? 24 ? 40 ? 32 ? 48 ? 72 ? 80 ? How 56? 6. How 64? 56? 7. In what number is 6 contained exactly once ? times? Twice? 5 times? 7 times ? 8 times? times? 10 times? 8. In what number is 7 contained exactly once? times I 6 times? 3 times? 5 times? 7 times? times ? 10 times ? 8 times ? 9. In what number is 8 contained exactly once? times ? 3 times ? 4 times ? 7 times ? 9 times ? 10 times ? 10. How much is 7 divided by 7 ? 14 divided by 7? 21 divided by 7? 28 divided by 7? 35 divided by 7? 42 divided by 7 ? 49 divided by 7? 56 divided by 7? times ? 8 times ? 6 divided by 6? 24 divided by 6 ? 36 divided by 6 ? 12 divided by 6? 18 divided by 6? 48 divided by 6? 42 divided by 6? 54 divided by 6 ? 3 9 4 9 5 6 8 divided by 8 ? 24 divided by 8 ? 40 divided by 8 ? 32 divided by 8? 16 divided by 8? 48 divided by 8? 56 divided by 8 ? 72 divided by 8 ? DIVISION. 47 60 divided by 6 ? 63 divided by 7 ? 64 divided by 8 ? 30 divided by 6 ? 70 divided by 7 ? 80 divided by 8 ? 11. How much is 6 x 11 ? 6 x 12 ? How much is 66 divided by 6? How much is 72 divided by 6 ? 12. How much is 11 x 7 ? 12 x 7 ? How much is 77 divided by 7 ? 84 divided by 7? 13. How much is 11 x 8? 12 x 81 How much is 88 divided by 8? 96 divided by 8 ? 14. 6 in 7 how many times, and what remainder? In 8? In 9 ? In 10 ? In 11 ? In 13 ? In 14 ? In 15? 16? 17? What are the remainders of numbers divided by 6 ? 15. 7 in 15 how many times, and what remainder ? In 16? 17? 18? 19? 20? 22? 23? 24? 25? 26? 27? What are the remainders of numbers divided by 7? 16. 8 in 9 how many times, and what remainder ? In 10? 11? 12? 13? 14? 19? 25? 26? 27? 28? 29? 30? 31? What are the remainders of numbers divided by 8? 17. Give the numbers from 1 to 100 which are divisible by 6. 18. Give the numbers from 1 to 100 which are divisible by 7. 19. Give the numbers from 1 to 100 which are divisible by 8. 20. 6 in 6 tens how many times ? In 12 tens ? In 18 tens ? In 24 tens ? In 36 tens ? In 60 tens ? 21. 6 in 6 hundred how many times? In 12 hun- dred ? In 18 hundred ? 22. 7 in seven* tens how many times ? In 14 tens? In 21 tens ? In 49 tens ? In 56 tens ? In 70 tens ? 23. 7 in 7 hundred? In 14 hundred? In 21 hundred ? 24. 8 in 8 tens? 16 tens? 24 tens? 32 tens? 56 tens ? 80 tens ? 4:8 DIVISION. 25. 8 in 8 hundred ? in 16 hundred ? in 24 hun- dred? 26. How much is 6 x 30 divided by 6? How much is 56 divided by 8 and the quotient multiplied by 8? 27. 6 in 40 how many times ? PROCESS. 40 is 36, and 4, 6 in 36 6 times. Hence 6 in 40 6 times and remainder 4. 28. 6 in 50 how many times ? 6 in 100 ? 8 in 50 ? 8 in 60 ? 8 in 90 ? 7 in 60 ? 7 in 80 ? 7 in 100 ? 8 in 100 ? LESSON IV. 1. If I wish to plant 36 trees in parallel rows of nine trees each, how many rows must I plant ? 27 trees will give how many rows of 9 trees each ? 45 trees how many rows ? 54 trees ? 72 trees ? 63 trees ? 81 trees ? 90 trees ? 2. A vessel was wrecked on a rocky coast, and there were more than a hundred men clinging to the wreck. The life-boat from the shore could only save ten men on each trip to the wreck. How many trips did its bold rowers have to make in order to save 30 men ? 40 men ? 60 men ? 100 men ? 80 men ? 3. How many 9's in 18 ? 27 ? 36 ? 45 ? 63 ? 54? 72? 81? 90? 4. How many 10's in 20? 80? 90? 70? 60? 50? 40? 30? 100? 5. What number contains 9 exactly once ? 3 times? Twice ? 5 times ? 6 times ? 8 times ? 7 times ? 4 times ? 9 times ? 10 times ? 6. What number contains 10 exactly 10 times? 9 times ? 8 times ? 7 times ? 6 times ? 5 times ? 4 times ? 3 times ? Twice ? 7. How much is 9 divided by 9 ? 10 divided by 10 ? DIVISION. 49 18 divided by 9 ? 20 divided by 10 ? 27 divided by 9 ? 30 divided by 10 ? 36 divided by 9 ? 40 divided by 10 ? 45 divided by 9 ? 50 divided by 10 ? 54 divided by 9 ? 60 divided by 10 ? 63 divided by 9 ? TO divided by 10 ? 72 divided by 9 ? 80 divided by 10 ? 81 divided by 9 ? 90 divided by 10 ? 90 divided by 9 ? 100 divided by 10 ? 8. How much is 11 x 9? 12 x 9 ? How many times does 99 contain 9 ? How many times does 108 contain 9? 9. How much is 11 x 10 ? 12 x 10 ? 10 in 110 how many times ? 10 in 120 how many times ? 10. 9 in 10 how many times, and what remainder ? In 11? 12? 13? 14? 15? 16? 17? In 19? 20? 21? 22? 23? 24? 25? 26? What are the remainders of numbers divided by 9? 11. 10 in 21 how many times, and what remainder? In 22? 23? 24? 25? 26? 27? 28? 29? In 41? 42? 43? 44? 45? 46? 47? 48? 49? What are the remainders of numbers divided by 10? 12. Give the numbers, from 1 to 100, which are divisible by 9. 13. Give the numbers, from 1 to 200, which are divisible by 10. 14. What figure do all numbers divisible by 10 end in? 15. 9 in 9 tens how many times ? In 18 tens ? 27 tens ? 36 tens ? 45 tens ? 90 tens ? 16. 9 in 9 hundred how many times ? 18 hundred ? 27 hundred? 36 hundred? 45 hundred? 63 hun- dred? 17. 10 in 10 tens how many times? In 20 tens? 30 tens ? 40 tens ? 50 tens ? 90 tens ? 50 DIVISION. 18. 10 in 20 hundred ? In 3000 ? 4000 ? 60 hun- dred ? In 7000 ? In 9000 ? 19. 9 in 86 how many times? PROCESS. 86 is 81 and 5. 9 in 81, 9 times. Hence, 9 in 86, 9 times, and 5 remainder. 20. 9 in 97 how many times? In 105? In 111? 113? In 960? 963? 999? In 456? 21. 10 in 770 how many times ? 220 ? 440 ? 1010? 77? 78? 101? 105? 362? 456? 22. When a number is not divisible by 10, which figure of the number is always the remainder ? 23. How much is 7 x 8 x 10, divided by 10? How much is 60 x 9, divided by 9 ? 24. How much is 9x8 + 3? 9x8 + 2? 9x 7 + 5? 9x6 + 7? 25. How much is 10 x 3 + 4 ? 10 x 4 + 5 ? 10x7 + 6? 10x8 + 9? LESSON V. 1. A workman, desiring to finish a piece of work speedily, labors 11 hours a day. In how many days will he have worked 33 hours ? 44 hours ? 55 hours ? 77 hours? 22 hours? 88 hours? 99 hours? 110 hours ? 2. Twelve eggs make a dozen. How many dozen eggs are 24 eggs ? 36 eggs ? 72 eggs ? 48 eggs ? 60 eggs? 84 eggs? 96egy one workman in 2 x 28, or 56 days. 2. What one workman can do in 56 days, can be done in 4 days by as many workmen as 56 ~ 4, 6>^ 14 workmen. 9. 15 laborers in 4 days do as much as 5 laborers in days ? 10. 24 laborers in 2 days do as much as 16 laborers in days ? 11. 12 laborers in 6 days do as much as 9 laborers in days? 12. 9 laborers in 10 days do as much as 30 laborers in days 3 64 MISCELLANEOUS. 13. 10 laborers in 18 days do as much as 60 laborers in days ? 14. 10 laborers in 12 days do as much as 20 labor- ers in days ? 15. 12 laborers in 12 days do as much as 18 laborers in days ? 16. 40 laborers in 3 days do as much as 6 laborers in days ? 17. 15 days' work of 3 men is equal to 9 days' work of men ? 18. 15 days' work of 4 men is equal to 5 days' work of men ? 19. 3 days' work of 10 men is equal to 16 days' work of men ? 20. 6 days' work of 6 men is equal to 12 days' work of men ? 21. 5 days' work of 15 men is equal to 15 days' work of men ? 22. 24 days' work of 5 men is equal to 12 days' w r ork of men ? 23. 24 days' work of 4 men is equal to 48 days' w^ork of men ? 24. How much will 30 pounds of sugar cost if 6 pounds cost 42 cents ? 25. If 10 pencils cost 30 cents, what will be the cost of 7 pencils ? of 9 ? of 15 ? of 12 ? 26. If 7 days' board cost 14 dollars, what will be the cost of 30 days' board ? 27. If 8 quarts of milk cost 48 cents, how much will 30 quarts cost? 28. A merchant bought 20 yards of cloth for 100 dollars ; he gave 10 yards of it for some flour which cost 10 dollars a barrel ; how many barrels did he get? 29. A greyhound, chasing a rabbit, is 30 yards be- hind the rabbit, and gains on him 6 yards every 3 minutes ; in how many minutes will he overtake him ? MISCELLANEOUS. 65 30. A man hired a laborer and agreed to give him 10 dollars for every 3 days' work ; how much did he have to pay him each week of 6 working days, and how much for each month of 4 weeks ? 31. If 6 oranges are worth 1 pine-apple, and 2 pine- apples are worth 1 melon, how many oranges are worth 4 melons ? 32. If 9 bushels of apples cost 18 dollars, how much do 100 bushels cost? 33. If 60 pounds of pork cost 300 cents, how much will 9 pounds cost ? 10 pounds ? 3 pounds ? 34. If a man travels 56 miles in 8 hours, how far does he travel in 3 hours ? 4 hours ? 5 hours? 35. On the 12th of November, 25 meteors appear and shoot across the sky every 2 hours ; how many ap- pear in 3 hours ? In 5 hours ? 36. A certain number of rations last 20 soldiers 5 days ; how long would they last 2 soldiers ? 50 sol- diers? 25 soldiers? 37. 40 days' rations for 5 men are 8 days' rations for men ? 38. 16 days' rations for 5 men are 10 days' rations for men ? 39. 18 days' rations for 6 men are 12 days' rations for men ? 40. 30 days' rations for 60 men are 18 days' rations for men ? 41. 3 days' rations for 90 men are 10 days' rations for men ? 42. 24 days' rations for 10 men are 3 days' rations for men ? 43. 16 days' rations for 6 men are 12 days' rations for men ? 44. 8 days' rations for 8 men are 2 days' rations men ? 5. 10 yards of cloth at 8 dollars a yard will pay how many barrels of flour at 5 dollars a barrel ? s 66 MISCELLANEOUS. 46. 9 times 8 are how many times 24 -=- 2 ? 47. 9 times 11 less 18 are how many times 36 48. 10 times 6 and 12 are how many times 40 8 ? 49. 12 times 7 and 15 are how many times 44 4? 50. 4 times 12 and 8 are how many times 49 7 ? 51. Bought 20 barrels of flour, at 6 dollars a barrel, and 6 yards of cloth, at 5 dollars a yard. Paid for the whole with 15 loads of hay. How many dollars did I get for each load of hay ? 52. If 4 cords of wood are worth 24 dollars, and 10 cords of wood are given for 40 thousand feet of plank, how many dollars will each thousand feet of plank cost ? 53. 5 men bought a horse for 63 dollars, and paid two dollars a week for keeping him ; at the end of 8 weeks, they sold him for 54 dollars. How much did each man lose by the bargain ? 54. A man bought 12 bales of cotton at 5 hundred dollars for every two bales. He sold all the cotton at 6 hundred dollars for every three bales. How many hundred dollars did he lose ? 55. What is the rent of 12 acres of land, that of 16 acres being 20 dollars ? 56. How long will 10 months' rations for 300 sol- diers, issued at the same rate, last a garrison of 500 soldiers \ MULTIPLES AND DIVISORS. 67 CHAPTER VI. MULTIPLES AND DIVISORS. LESSON I. 1. 12 contains 6 an exact number of times. By adding 6 to itself once, or multiplying it by 2, we obtain 12. Hence 12 is called a multiple of 6. Thus, 24 is a multiple of 6, and 50 is a multiple of 5. 2. When is one number said to be a multiple of another number ? ANS. When one number contains another number an exact nuinber of times, it is said to be a multiple of that number. 3. 6 divides 12 exactly, and hence is called a divisor of 12, or one of its factors. In the same manner, 4 is & factor or divisor of 12. 5 is one of the factors or divisors of 60. 4. What is meant by a factor or divisor of a given number ? ANS. Any number which is contained an exact nujnber of times in the given number. 5. Every number contains itself once. 5 contains 5 once, 100 contains 100 once. Hence, every number is a multiple and divisor of itself. 6. What number divides exactly all numbers? How often is 1 contained in 5 ? In 6 ? In 500 ? 7. What two divisors has every number, at least ? ANS. The number itself, and one. 8. Give 4 numbers which are multiples of 9. 9. Give 5 numbers which are multiples of 10. Of 11. Of 12. 68 MULTIPLES AND DIVISORS. 10. Give 3 multiples of each of the numbers, 20, 30, and 40. 11. Find some numbers which are factors or divisors of 15. Of 20. Of 40. Of 50. Including one and the numbers themselves, respec- tively 12. Find the 3 divisors of 4. Of 9. Of 25. Of 49. 13. What are the four divisors of 8 ? of 10 ? of 14? 15? 21? 22? 26? 33? 34? 35? 38? 39? 46? 51? 55? 57? 58? 62? 65? 69? 74? 77? 82? 85? 86? 87? 91? 93? 94? 95? 14. What are the five divisors of 16 ? of 81 ? 15. What are the six divisors of 12 ? 18 ? 20 ? 28? 32? 44? 45? 50? 52? 63? 68? 75? 76? 92? 98? 99? 16. What are the seven divisors of 64? 17. What are the eight divisors of 24? of 30? 40 ? 42 ? 54 ? 56 ? 66 2 70 ? 78 ? 88 ? 18. What are the nine divisors of 36 ? of 100 ? 19. What are the ten divisors of 48 ? of 80 ? 20. What are the 12 divisors of 60 ? of 72 ? of 84 ? of 90 ? of 96 ? LESSON II. A number which has several divisors is called a common multiple of these divisors. Thus, 10 is a common multiple of 2 and 5, because 2 and 5 are both contained in 10 an exact number of times. 4 is a common multiple of 2 and 4. 12 is a common multiple of 1, 2, 3, 4, 6, and 12. 1. What is a common multiple of two or more numbers ? ANS. It is any number which contains each of the given numbers an exact number of times. 2. Find some common multiples of 5 and 4. Of 6, 3, and 2. Of 3 and 4. MULTIPLES AND DIVISORS. 69 3. What is the least common multiple of two or more numbers ? ANS. It is the smallest number which these num- bers will exactly divide. 4. What is the least common multiple of 2 and 3 ? of 3 and 4 ? of 4 and 5 ? of 5 and 10 ? 5. of 2 and 4 ? of 3 and 5 ? of 5 and 6 ? of 5 and 100? 6. of 2 and 5'? of 3 and 6 ? of 4 and 7 ? of 6 and 0? 7. of 2 and 6 ? of 3 and 7 ? of 4 and 8 ? of 7 and 1? 8. of 2 and 7? of 3 and 8 \ of 4 and 9 ? of 8 and 9. of 2 and 8 ? of 3 and 9 ? of 4 and 10 ? of 9 id 30 ? 10. of 2 and 9 ? of 3 and 10 ? of 4 and 11 ? of and 8 ? 11. What is the least common multiple of 2, 3, and PROCESS. The least common multiple of 2 and 3 1 6, of 6 and 4 is 12. Hence , 12 is the least common \dtiple of 2, 3, and 4. 12. What is the least common multiple of 2, 3, and 5 ? of 3, 4, and 5 ? of 2, 3, and 6 ? of 3, 4, and 6 ? of 2, 3, and 7 ? of 3, 4, and 7 ? 13. What is the least common multiple of 2, 3, 4, id 6? PROCESS. The least common multiple of 2 and 3 6, of 6 and 4 is 24, ^ 24 #;i6? 6 is 24. .SWtf, ^ ast common multiple of 2, 3, 4, 6 is 24. 14. What is the least common multiple of 2, 3, 4, 5 ? of 3, 4, 5, 6 ? of 4, 5, 6, 8 ? of 2, 3, 4, 7 ? of 3, 4, 5, 10 ? of 4, 5, 6, 9 ? of 2, 3, 4, 10 ? of 3, 4, 5, 8 ? of 4, 5, 6, 10 ? 15. What is the least common multiple of 2, 3, 4, 70 MULTIPLES AND DIVISORS. LESSON III. 1. Give two or more numbers of which 3 is a divisor. 3 is called a common divisor or common factor of these numbers. 2. What numbers are common divisors of 8 and 12? ANS. 2 and 4 because they divide 8 and 12 with- out a remainder. 3. What numbers are common divisors of 6, 12, and 24 ? ANS. 2, 3, and 6. 4. When is a number said to be a common divisor or common factor of two or more numbers ? ANS. When it is contained an exact number of times in each of these numbers. 5. What number is a common divisor of all num- bers ? 6. Which is the greatest common divisor of 8 and 12? ANS. 4. Because it is the greatest number which divides 8 and 12 without a remainder. 7. What is the greatest common divisor of 6, 12, and 24 ? ANS. 6. 8. What is the greatest common divisor of two or more numbers ? ANS. The greatest number which is contained ex- actly in these numbers. 9. What is the greatest common divisor of 15 and 20? of 6 and 24 ? of 12 and 30 ? of 25 and 45 ? of 22 and 33 ? 10. What is the greatest common divisor of 4, 8, and 16? PROCESS. The greatest common divisor of 8 and 16 is 8 ; of 8 and 4 -is 4. Hence , 4 is the greatest common divisor of 4, 8, and 16. MULTIPLES \XD DIVISORS. 71 11. What is the greatest common divisor of 5, 10, and 15 ( of 12. What is the srreatest common divisor of IS and of '24: and 3' and 54: i of 24: and 100* LESSOR IV. A nnmber which has no other divisors except the number 1 and the number itself is called a prime number. Thus, 2 has no divisor except itself and 1 ; 3 has no divisor except 3 and 1 ; 5 has no divisor ex- cept 5 and 1. tire. Hence, 2, 3. and 5 are prime num- bers, 1 is also a prime number. 1. Are any of the even numbers which are greater than 2, prime numbers Why not \ 2. Find the prime numbers from the number 1 to the number 3. Find the prime numbers between 25 and 50. 4:. Find the prime numbers between 50 and 5. Find the prime numbers between 75 and The numbers which are not prime are the prod:: of two or more numbers: I > _ _ > _ x 3. _ 4:, or 2 x 2 x 2. i-i >- x 3, or 2 x 3, or 2 x 2 x 2 x 3. The divisors or fac: .\re called the//r/ffi fact 2. 2, 2, 3. the /////!<:- factors of L'4r. 6. 2i is the continued product of what 4: numK 9 is the product of what 2 prime numbe il - is the continued product of what three prime fact-; - 7. What are the prime factors of any number ? Axs. The smallest numbers whose continued pro- duct id II given number. ^ Find the 2 prime factors of each of the number- , U, 15, 21, I":. "". --. B&, ^ 87, (Thirty-four numbt 9. Find 3 prime f :' each of the nuniK 72 FRACTIONS. 12, 18, 20, 27, 28, 30, 42, 44, 45, 50, 52, 63, 66, 68, 70, 75, 76, 78, 92, 98, 99. (Twenty-two numbers.) 10. What are the 4 prime factors of 16, 24, 36, 40, 54, 56, 60, 81, 84, 88, 90, 100 ? (Twelve numbers.) 11. What are the 5 prime factors of 32, 48, 72, 80 ? (Four numbers.) 12. Find the 6 prime factors of each of the num- bers, 64 and 96. (Two numbers.) 13. There are 32 + 22 + 12 + 4+2 numbers, from 1 to 100, which have factors ; how many are there ? 14. How many prime numbers from 1 to 100 ? 15. What number multiplied by itself gives 4? 25? 9? 49? 16? 36? 64? 81-? 100? 121? 144 ? 169 ? 196 ? CHAPTER VII. FRACTIONS. LESSON I. Halves, Thirds, and Fourths, or Quarters. 1. IF a line be divided into two equal parts, what is each one of these parts called ? ANS. One-half of the line. 2. How do you get the half of an apple or orange, or any thing ? ANS. Divide it into two equal parts and take one of these parts. 3. How many half cents in 1 cent ? How many half cents in two cents ? How many half apples in FRACTIONS. 73 three apples? How many half cents in 50 cents? How many half dollars in 8 dollars ? 4. How many halves in 1 ? 2 ? 3 ? 4 ? 5 ? 6 ? 7 ? 8 ? 9 ? 10 ? 61 ? 40 ? 500 ? 5. How do you find the number of halves in any number ? ANS. Multiply the number by 2. 6. How many half apples can you make of 2 half apples? How many cents are equal to 10 half cents? How many dollars do 12 half dollars make? 7. How many ones in 2 halves ? 4 halves ? 8 halves? 6 halves 10 halves? 12 halves? 24 halves ? 48 halves ? 100 halves ? 18. How do you get the number of ones or units in y number of halves ? ANS. Divide the number of halves by 2. 9. How many half apples in 3 apples and one half apple ? How many dollars in 5 dollars and a half dollar ? How many half yards of cloth in 7 yards and a half yard ? 10. How many halves in 10 and one-half? 11 and one-half? 15 and one-half? 50 and one-half? 60 and one-half? 4 and one-half? 19 and one-half? 11. How many apples in 3 half apples? How many dollars in 7 half dollars ? What remains over in each case? 12. How many ones in 7 halves? 9 halves? 11 halves? 13 halves? 27 halves? 99 halves? 57 halves ? 45 halves ? 23 halves ? 31 halves ? t!3. 7 divided by 2 is how much? ANS. 3 and one-half. 14. 2 in 27 how many times ? 2 in 99 ? 2 in 31 ? n 23 ? 2 in 81 ? 2 in 11 ? 15. 1 half of 2 apples is - - ? one-half of 3 dol- 's is how much ? 16. How much is one-half of 2 ? of 3 ? of 5 ? of 74 FRACTIONS. 6? of 7? of 8? of 9? of 10? of 11? of 12? of 25? of 100? 50? 40? 32? 22? 400? 61? 17. How do we get the half of a number ? ANS. Divide it by 2. 18. 3 is the half of what number? 6 is the half of what number ? the half of what number is 7 ? 9? 12? 20? ^30? 25? 60? 15? 19? PROCESS. 3 is the half of two 3's, or 2 x 3. 7 is the half of 2 x 7, &c., &c. 19. How much is three halves of 12 ? PROCESS. One-half of 12 is 6 ; hence, three halves of 12 is three times 6. 20. How much is three halves of 24 ? of 50 ? of 30? of 18? of 20? 21. How much is 7 halves of 20 ? 18 ? 30 ? 12 ? 22. How much is 9 halves of 18 ? 24 ? 10 ? 90 ? 23. How much is 11 halves of 12 ? 14 ? 30 ? 22 3 24. If a line be divided into three equal parts, what is each part called ? ANS. One-third. 25. How do you get the third of an apple, orange, or of any thing ? 26. How do you get two-thirds of any thing ? 27. How many thirds of an apple in one apple ? in 2 apples ? How many thirds of a cent in 3 cents ? How many thirds of a yard of cloth in 6 yards of cloth ? 28. How many thirds inl? 2? 3? 4? 5? 8? 7? 6? 9? 10? 30? 40? 12? 11? 300? 29. How do you find the number of thirds in any number ? 30. How many apples do 3 thirds of an apple make ? How many dollars are equal to 6 thirds of a dollar? How many oranges do 12 thirds of an orange make ? FRACTIONS. 75 31. How many ones in 3 thirds ? 6 thirds ? 9 thirds? 15 thirds? 12 thirds? 18 thirds? 24 thirds ? 21 thirds ? 27 thirds ? 99 thirds ? 60 thirds ? 32. How do you find the number of ones or units in any number of thirds ? 33. How many thirds of an orange in 3 oranges and 1 third of an orange ? in 3 oranges and 2 thirds ? How many thirds of a bushel of meal in 6 bushels and one-third of a bushel ? How many thirds of a dollar in 8 dollars and 2 thirds of a dollar ? 34. How many thirds in 3 and one-third ? in 3 and 2 thirds ? in 5 and 2 thirds ? in 30 and a third ? 21 and 2 thirds ? in 40 and one-third ? in 11 and 2 thirds ? in 100 and one-third ? 35. How many oranges can you make of 4 thirds of an orange ? How many dollars do 8 thirds of a dollar make? How many thirds remain in each case? How many bushels of meal do 10 thirds of a bushel make ? What remains ? 36. How many ones in 4 thirds ? 5 thirds ? 7 thirds? 8 thirds? 11 thirds? 13 thirds? 16 thirds? 20 thirds ? 61 thirds ? 100 thirds ? 37. 7 divided by 3 is how much ? ANS. 2 and one-third. 38. 3 in 13 how many times? in 14? 80? 62? 44? 22? 8? 39. How much is one-third of 2 ? Show by the picture above that one-third of two is 2 thirds of one. How much is one-third of 3 ? 4 ? 5 ? 6? 7 ? 8 ? 9? 10? 11? 12? 24? 27? 15? 18? 30? 60? 90? 600? 900? 99? 22? 17? 31? 40. How do you find one-third of any number ? How much is 2 thirds of 6 ? PROCESS. One-third of is 2. Hence, 2 thirds of 6 is 2 x 2, or 4. 41. How much is two-thirds of 21 ? 2 thirds of 9 ? 2 thirds of 5 ? of 7 ? of 100 ? of 60 ? 76 FRACTIONS. 42. How much is 4 thirds of 6 ? PROCESS. One-third of 6 is 2. Hence, 4 thirds of 6 is 4: x 2, or 8. 43. Which is the greater, 4 thirds of a number or the number itself? How much is 3 thirds of 6 ? 44. How much is 4 thirds of 21 ? 24 ? 27 ? 60 ? 15? 10? 12? 45. How much is 5 thirds of 5 ? 12 ? 21 ? 24 ? 27? 60? 33? 46. How much is 6 thirds of 27 ? 9 ? 12 ? 18 ? 24? 30? 42? 36? 47. How much is 10 thirds of 15 ? 12 ? 21 ? 27 ? 20? 60? 90? 99? 48. 2 is one-third of what number ? 6 is one-third of what number ? 49. One-third of what number is 7 ? 9 ? 12 ? 8 ? 20? 30? 60? 19? 15? 100? 300? 600? PROCESS. 2 is one-third of three 2's, or 3 times 2. 6 is one-third of 3 times 6, dec. 50. If a line be divided into 4 equal parts, what is each one of these parts called ? ANS. One-fourth of the line, or sometimes one- quarter of the line. 51. How do you get one-fourth or a quarter of an apple or orange, or of any thing ? How do you get 2 fourths or quarters ? 3 fourths or quarters ? ANS. Divide it into four equal parts, and take one of the parts, two of the parts, and three of the parts, respectively. 52. How many fourths of an apple in one apple ? How many fourths of a bushel of meal in 2 bushels of meal ? How many fourths of a pint of wine in one pint of wine ? How many quarter dollars in 5 dollars ? 53. How many fourths in 1 ? 2 ? 3 ? 4 ? 5 ? 6 ? FRACTIONS. 77 7? 8? 9? 10? 11? 12? 13? 15? 20? 30? 40? 100? 200? 202? 54. How do you find the number of fourths in any Dumber ? 55. How many fourths in 3 and one-fourth ? PROCESS. There are 12 fourths in 3, and these, added to one-fourth give 13 fourths. 56. How many fourths in 6 and 2 fourths ? 7 and 3 fourths ? 20 and one-fourth ? How many quarter dollars in 10 dollars and 3 quarter dollars? How many fourths in 30 and 3 fourths ? in 100 and 2 fourths ? in 12 and 3 quarters ? 5 7. How many oranges do 4 fourths of an orange make ? How many dollars do 12 quarter dollars make ? How many gallons of wine do eight quarter gallons make ? 58. How many ones in 4 fourths ? 8 fourths? 12 fourths ? 24 fourths ? 32 fourths ? 28 fourths ? 60 fourths ? 40 fourths ? 400 fourths ? 88 fourths ? 59. How do you find the number of ones in any number of fourths ? 60. How many oranges do 5 quarter oranges make ? How much over? 61. How many dollars do 6 quarter dollars make? How much over ? 62. How many yards of cloth do 17 quarter yards make ? How much over ? 63. How many ones in 5 fourths? 6 fourths? 7 fourths ? 21 fourths ? 22 fourths ? 61 fourths ? 49 fourths ? 37 fourths ? 39 fourths ? 64. If we divide 9 apples among four boys, how many whole apples would each boy get ? In order to give each boy an equal share, what must we do with the remaining apple ? 9 divided by 4 is how much ? , ANS. 2 and one fourth. 65. If we divide 10 apples equally among 4 boys, what would be the share of each one ? 78 FRACTIONS. ANS. 2 apples and 2 fourths of an apple. 66. If we divide 11 apples equally among 4 boys, what would be the share of each ? 67. 4 in 13 how many times? in 14 ? 15? 22? 21? 25? 27? 30? 62? 63? 43? 103? 101? 401? 68. How much is one-fourth of 2 ? of 3 ? Show by the picture of lines above that one-fourth of 2 is 2 fourths of 1. Show that one-fourth of 3 is 3 fourths of 1. 69. How much is one-fourth of 2 ? 3 ? 4 ? 5 ? 6? 7? 8? 9? 10? 11? 12? 13? 16? 18? 20? 44? 60? 64? 80? 400? 444? 70. How do you -find one- fourth of any number ? 71. How much is 2 fourths of 8 ? 3 fourths of 8 ? 4 fourths of 8 ? 5 fourths of 8 ? 10 fourths of 8 ? 72. 5 fourths of eight is how many times 8 ? ANS. Once 8 and one-fourth of 8. 73. How much is 3 fourths of 12 ? of 9 ? of 24 ? of 28? 32? 80? 100? 400? How much is 2 fourths of 8 ? 16 ? 12 ? 40 ? 100 ? 400 ? 74. How much is 5 fourths of 56 ? 60 ? 92 ? 80 ? 20? 28? 36? 40? 48? 75. How much is 7 fourths of 12 ? 96 ? 20 ? 16 ? 24? 52? 40? 44? 76. How much is 10 fourths of- 8 ? 12 ? 24 ? 6 ? 16? 80? 400? 77. 2 is one-fourth of what number ? 3 is one- fourth of what number? One-fourth of what num- beris4? 5? 6? 7? 8? 9? 10? 11? 12? 60? 40? 100? 200? 15? 400? 900? 78. 8 is -what part of 16 ? 24 ? 32 ? 6 is what part of 24 ? 12 ? 18 ? 7 is what part of 21 ? 28 ? 14? 10 is what part of 40? 20? 30? 60 is what part of 120 ? 240 ? 180 ? 9 is what part of 27 ? 36 ? 18 ? 12 is what part of 36 ? 15 is what part of 60 ? 14 is what part of 28 ? 100 is what part of 400 ? FRACTIONS. 79 79. 3 halves is 3 -f- ? 5 halves is 5 -4- ? 4 thirds is 4 + i 5 fourths is 5 -f- ? 100 fourths is 100 H- ? We use figures to write briefly halves, thirds, and fourths, or in general, fractions. (The sign signifies equal to.) 3 halves is written f ; 5 fourths is written ; 20 thirds is written 2 ^-. 80. What does the number above the line si^nd for? ANS. It gives the number of halves, fourths, or thirds. 81. What does the number below the line show ? ANS. To write halves we put 2 below the line / to write thirds we put 3 ; to write fourths we put 4 below the line. 82. Give the figures and their places which will represent 7 halves, 10 thirds, 14 fourths. Read the frflftinnq - 6 -- 4_4 2 - 7 3. 5. & ,2 ) 35 45453' 83. 5 and one-half, and 2 thirds, 8 and 3 fourths, &c., are written without any sign between the frac- tion and the whole number, thus : 5|-, 6f, 8f, and these are called mixed numbers. Write 100 and one-fourth, 20 and 2 fourths, 5 and 2 thirds, 7 and a half. Read 25|, 42i, 8j. NOTE. In the chapters preceding Chapter VII. the word number means whole number. In this and succeeding chapters it is applied to fractions as well as whole numbers. 80 FRACTIONS. LESSON II. 1. If a line be divided in five equal parts, what do we call one part of it ? ANS. One-fifth of the line. 2. If a line be divided into 6 equal parts ? Seven equal parts ? ANS. One part is called one- sixth and one-seventh, respectively. 3. How do you get one seventh of anything? one- sixth ? one-fifth ? 2 sevenths ? 3 sevenths ? 4 sevenths ? 5 sevenths ? 2 fifths ? 3 fifths ? 4 fifths ? 3 sixths? 5 sixths? 4. If we conceive the number 1 divided into five equal parts, what will these parts be called ? If it is divided into six equal parts, what do we call them ? into 7 equal parts ? 5. How many fifths inl? 2? 3? 4? 5? 6? 7? 8? 9? 10? 11? 12? 20? 15? 40? 60? 24? 32? 100? 200? 6. How many fifths in 2? 3? 4? 5? 6? 7? 8? 9? 12? 10? 11? 20? 15? 40? 30? 31? 50 ? 100 ? 400 ? 7. How many sevenths inl? 2? 3? 4? 5? 6? 7? 8? 9? 10? 11? 12? 75? 16? 19? 20? 30? 41? 100? 120? 8. How do you find the number of fifths in any num- ber ? the number of sixths ? the number of sevenths ? 9. How many apples do 5 fifths of an apple make ? 6 fifths of an apple ? How many dollars are equal to 12 sixths of a dollar? to 14 sevenths of a dollar ? 10. How many ones in 5 fifths ? 6 fifths ? 7 fifths ? 8 fifths ? 9 fifths ? 10 fifths ? 15 fifths ? 20 fifths ? FRACTIONS. 81 25 fifths ? 26 fifths ? 2T fifths ? 28 fifths ? 29 fifths ? 30 fifths ? 60 fifths ? 100 fifths ? 200 fifths ? 11. How many ones in 6 sixths ? 7 sixths ? 8 sixths ? 9 sixths ? 10 sixths ? 11 sixths ? 12 sixths 2 21 sixths? 30 sixths? 36 sixths? 48 sixths? 60 sixths? 72 sixths? 100 sixths? 31 sixths? 32 sixths ? 34 sixths ? in 600 sixths ? 12. How many ones in 7 sevenths ? 8 sevenths ? 9 sevenths? 10 sevenths? 11 sevenths? 12 sevenths? 13 sevenths ? 14 sevenths ? 15 sevenths? 21 sevenths ? 42 sevenths ? 35 sevenths ? 70 sevenths ? 84 sevenths ? in 100 sevenths? 490 sevenths ? 210 sevenths ? 13. How do you find the number of ones in any number of fifths ? in any number of sevenths ? in any number of sixths ? 14. 7 in 8 how many times? in 10 ? in 26 ? in 30 ? 15. 6 in 13 how many times ? in 14 ? in 15 ? in 28 ? in 29 ? 16. 5 in 11 how many times ? in 12 ? in 13 ? in 24 ? in 39 ? 17. If I wish to divide 13 oranges among 5 boys, how many oranges and what parts of an orange would the equal share of each boy be ? What would be the equal share of each of 6 boys ? of each of 7 boys ? 18. How many fifths in 3 and one-fifth? 20 and 3 fifths ? 60 and 4 fifths? 5 and one-sixth how many sixths y4 and 3 sixths ? 100 and 5 sixths? 8 and 2 sevenths how many sevenths ? 10 and 3 sevenths ? 1 5 and 5 sevenths ? 40 and 6 sevenths ? 19. How much is one-fifth of 2 ? Draw lines on 3ur slate, and show that one-fifth of 2 is 2 fifths of ne. Show that one-sixth of 5 is 5 sixths of 1. liow that one-seventh of 3 is equal to 3 sevenths '1. 20. How much is one-fifth of 3 ? 4? 5? 10? >? 20? 24? 25? 30? 31? 35? 37? 40? I? 50.? 100? 200? 500? 150? 250? 82 FRACTIONS. 21. How much is one-sixth of 2 ? 3 ? 4 ? 5 ? 6 ? 12? 13? 14? 18? 24? 28? 29? 30? 36? 58? 72? 70? 100? 600? 120? 300? 22. How much is one-seventh of 2 ? 3 ? 4 ? 5 ? 6? 7? 11? 12? 13? 14? 28? 30? 35? 36? 42? 49? 70? 63? 100? 84? 490? 700? 23. How much is 2 fifths of 10 ? 3 fifths of 45 ? 4 fifths of 50? 6 fifths of 30? 4 fifths of 80? 5 fifths of 25? 24. How much is 3 sixths of 12 ? 4 sixths of 18 ? 5 sixths of 96 ? 6 sixths of 72 ? 7 sixths of 42. 25. How much is one-seventh of 84? 2 sevenths of 84 ? 3 sevenths of 84 ? 4 sevenths of 21 ? 5 sevenths of 28 ? 6 sevenths of 35 ? 7 sevenths of 98 ? 10 sevenths of 70 ? 26. 3 is one-fifth of what number ? One-fifth of what number is 4 ? 5? 6? 7? 8? 9? 10? 12? 60? 100? 25? 33? 200? 27. 3 is one-sixth of what number ? One-sixth of what number is 2 ? 4 ? 5 ? 6 ? 7? 8? 9 ? 10 ? 11? 12? 13? 14? 15? 20? 22? 30? 40? 50? 100? 45? 200? 400? 28. 2 is one-seventh of what number? One- seventh of what number is 3? 4? 5? 6? 7? 8? 9? 10? 11? 12? 13? 14? 20? 21? 30? 33? 40? 100? 200? 300? 29. What part of 15 is 3? What part of 30 is 5? 6? What part of 42 is 6? 7? WhaP^rt of 35 is 5 ? 7 ? What part of 72 is 12 ? What part of 63 is 9 ? of 80 is 16 ? 8 is what part of 16 ? 24 ? 32? 40? 48? 56? 1 is what part of 2? 3? 4? 5 ? 6 ? 7 ? 100 is what part of 200 ? 300 ? 400 ? 500 ? 600 ? 700 ? 30. 4 fifths of 1 is one-fifth of 4, or 4 divided by what ? 6 sevenths is one-seventh of 6, or 6 divided by what I 5 sixths is one-sixth of 5, or 5 divided by what \ 31. 4 fifths is written f 6 sevenths is written ^ ; 4 sixths is written |. What does the number under FRACTIONS. 83 the line show ? What does the number over the line ? What figures, and how placed, stand for 1 sixth? 2 fifths? 3 sevenths? 4 sevenths? 3 sixths? 1 fifth ? 1 seventh ? 4 and 2 sevenths ? 5 and 5 sixths? 100 and 3 fifths? 32. Read the following fractions: J, f, J T % ^S Y-? V, f, I, J, -4*, 47i, 3i, 5f, 20i. LESSON III. 1. If a line be divided into 8 equal parts, what is each one of those parts called ? ANS. One-eighth of the line. If the line is divided into nine equal parts, what is each part ? ANS. One-ninth. If the line be divided into 10 equal parts, what is each part? ANS. One-tenth of the line. 2. How do you find the eighth, ninth, and tenth of any thing? How do you get 4 eighths of a thing? 3 ninths ? 7 tenths ? 3. How many eighths of a dollar in one dollar? in 2 dollars ? 4 dollars ? How many ninths of a gallon of wine in one gallon ? 3 gallons ? How many tenths of a dollar in 5 dollars? 4. How many eighths inl? 2? 3? 4? 5? 6? 7? 8? 9? 10? 11? 12? 20? 30? 40? 22? 35? 44 ? 100 ? 200 ? 5. HW many ninths inl? 2? 3? 4? 5? 6? 7? 8? 9? 10? 11? 12? 13? 14? 15? 16? 20? 24? 30? 40? 100? 120? 300? 900? 6. How many tenths inl? 2? 3? 4? 5? 6? 7? 8? 9? 10? 11? 12? 13? 14? 15? 16? 20? 37? 49? 56? 100? 240? 500? 1000? 7. How many bushels do 16 eighths of a bushel make ? How many dollars are equal to 21 dimes or tenths of a dollar ? How many yards of cloth are Iual to 27 ninths of a yard ? 8. How many ones in 8 eighths ? 10 eighths ? 12 84: FRACTIONS. eighths ? 16 eighths ? 24 eighths ? 32 eighths ? eighths ? 35 eighths ? 39 eighths ? 40 eighths ? eighths ? 56 eighths ? 64 eighths ? 71 eighths ? eighths ? 100 eighths ? 800 eighths ? 9. How many ones in 9 ninths ? ninths? 18 ninths? 25 ninths? ninths? 36 ninths? 38 ninths? ninths? 54 ninths? 58 ninths? ninths? 72 ninths? 81 ninths? ninths ? 126 ninths ? 1.0 ninths? -27 ninths? 45 ninths ? 63 ninths? 90 ninths? 33 46 80 17 30 50 69 100 10. How many ones in 10 tenths ? 14 tenths? 20 tenths? 22 tenths? 30 tenths? 36 tenths? 40 tenths? 45 tenths? 50 tenths? 53 tenths? 60 tenths? 61 tenths? 70 tenths? 72 tenths? 80 tenths? 88 tenths? 90 tenths? 99 tenths? 100 tenths? 150 tenths? 200 tenths ? 305 tenths? 1000 tenths ? 11. If yon wish to divide 17 pounds of candy equally among 8 boys, how many pounds and what parts of a pound would you give to each? If you divided 17 pounds of candy equally among 9 boys, what would be the share of each ( If it was divided equally among 10 boys, what would be the share of each ? 12. How many eighths in 5 and 2 eighths ? in 20 and 5 eighths ? in 3 and 7 eighths ? 10 and 3 eighths? How many ninths in 5 and 2 ninths ? 10 and 6 ninths ? 12 and 8 ninths? How many tenths in 6 and 3 tenths ? in 25 and 7 tenths? in 30 and 9 tenths? 13. How much is 1 eighth of 3? Show by means of lines that 1. eighth of 3 is 3 eighths of 1. Show that 1 ninth of 2 is 2 ninths of 1. Show that 1 tenth of 3 is 3 tenths of 1. 14. How much is 1 ninth of 2? 3? 4? 5? 6? 10? 15? 9? 20? 24? 18? 27? 36? 45? 54? 63? 72? 75? 81? 88? 90? 100? 900? 1800? 15. How much is 1 eighth of 2 ? 3 ? 4 ? 5 ? 10? 15? 16? S? 21? 24? 32? 36? 40? 44? 48? 50? 56? 64 2 72? 80? 96? 97? 100? 800? 1600 cu . )0? FRACTIONS. 85 1,6. How much is 1 tenth of 2 ? 3 ? 4 ? 5 ? 6 ? 10? 12? 14? 17? 19? 20? 30? 35? 48? 60? 67? 70? 80? 89? 90? 100? 111? 500? 120? 600 ? 1000 ? 17. How much is 1 'eighth of 24 ? 2 eighths of 24 ? 3 eighths of 24 ? 4 eighths of 16 ? 6 eighths of 40 ? 7 eighths of 32 ? 2 eighths of 72 ? 10 eighths of 80 ? 18. How much is 1 ninth of 27? 2 ninths of 27? 5 ninths of 27 ? 10 ninths of 27? 4 ninths of 36? 6 ninths of 72 ? 8 ninths of 100 ? 19. How much is 1 tenth of 50 ? 5 tenths of 50 ? 6 tenths of 50 ? 11 tenths of 50 ? 3 tenths of 40? 4 tenths of 70? 7 tenths of 210? 12 tentfis of 120? 9 tenths of 110? 120. 3 is one-eighth of what number ? One-eighth of hat number is 4? 2? 5? 7? 6? 8? 9? 10? H 14? 25? 100? 200? 80? 21. One-ninth of what number is 1 ? 2 ? 3 ? 4 ? ? 6? 7? 8? 10? 12? 19? 22? 31? 100? )0? 90? 22. One-tenth of what number is 1 ? 2? 3? 4? 5? 6? 8? 9? 10? 11? 12? 17? 20? 36? 45? 100 ? 120 ? 200 ? 23. 2 is what part of 20? 18? 16? 14? 12? 10? 8? 6? 4? 2? 5 is what part of 10 ? 5? 20? 15? 30 ? 25 ? 40 ? 35 ? 45 ? 50 ? 1 is what part of 8 ? ;10 ? 10 is what part of 80 ? 100 ? 90 ? 100 is hat part of 100 ? 900? 800? 1000? 24. How do you express in figures one-ninth ? one- snth ? one-eighth ? five-eighths ? six-ninths ? four- inths ? eight and three-tenths ? nine and four-eighths ? o hundred and seven-tenths. 25. Eead the fractions |, -f^-, f , ^ 5|, 7-f, 8^-, M$. 26. The numbers above the lines in a fraction are ailed what ? ANS. The numerators. 86 FRACTIONS. 27. The numbers below the line are called what ? ANS. The denominators. 28. The denominator shows in how many parts the unit is divided. It denominates or names the parts. And the numerator shows hovP many of these parts form the fraction. It numbers the parts taken. In how many parts is the unit divided, and how many of these parts are taken in -f ? ? f ? ^ ? I ? f i ? 29. If we divide any thing into 11 equal parts, what is each one of these parts called ? Into 12 equal parts ? Into 20 equal parts? Into 35 equal parts? Into 60 equal parts ? Into 100 equal parts ? 30. How many twelfths in 3 ? 4? 5? 12? How many twentieths in 1? 2? 3? 20? How many Imndredths in 5 ? 6? 7? 10? 31. How many ones in ff ^, fjft, |f ? 32. How much is -^ of 12 ? 24:? 25 '{ 60 ? How much is ^5- of 60 ? of 90 ? 120 ? How much is of 200? 300? 360? 33. We know now three sorts of fractions. 1st. Proper fractions, as ^, f , f , -^, in which the numera- tor is less than the denominator. 2d. Improper frac- tions, as |-, f, -2^-, -{-f , -2-lp-, in which the numerator is equal to or is greater than the denominator. 3d. Mixed numbers, as 4f , 5^-, 7|, &c., made up of whole numbers and fractions. REMARK. An improper fraction always stands for either a whole or mixed number. 34. If you increase the denominator of a fraction, do you increase or diminish the fraction ? If you increase the numerator of a fraction, do you increase or dimin- ish the fraction ? FRACTIONS. 87 LESSON IV. 1. If an orange costs 9 cents, what is the cost of % of it? f of it? 2. If a bushel of potatoes costs 60 cents, what is the cost of ^ of a bushel ? of f of a bushel ? of 4 of a bushel? off of a bushel? of f of a bushel ? What is the cost of T V of a bushel ? of -^ of a bushel ? of -J- of a bushel ? of f of a bushel ? of T ^- of a bushel ? of T 7 T of a bushel ? of ^ of a bushel ? of V of a bushel ? of fg- of a bushel ? 3. If an acre of land costs 72 dollars, what is the cost of -| of the acre ? of f of it ? of ^ of it? of -^ of it? of i of it? of \r of it? off of it? off of it? of T *g-ofit? of -fa of it? off of it? 4. If a railway car travels 40 miles an hour, how many miles does it go in ^ of an hour ? in -f- of an hour ? in -|~J of an hour? in ^ of an hour ? 5. If a man earns 48 dollars a month, how much does he earn in % of a month ? in f of a month ? in -fa of a month ? in f of a mouth ? in |- of a month ? in ^ of a month? in f of a month ? in -^ of a month ? in -/ of a month ? 6. If a man can do a piece of work in 90 days, how long will it take him to do the work ? ^ of the work ? | of the work ? -j 3 ^ of the work ? How long will it take him to do -fa of the work ? f of the work ? f of the work ? f of the work ? -^ of it ? ^ of it ? f -| of it ? 7. 84 gallons of water flow from a spring in one hour, how many gallons flow out in ^ an hour '( in f of an hour? in*f of an hour ? in f of an hour ? in f of an hour? in \% of an hour? in ||- of an hour? in ^\ of an hour ? in |-f of an hour ? in ^f of an hour ? 8. If -^ of an acre of land costs 5 dollars, what is the whole acre worth ? What is -$ of the acre worth ? fa of the acre ? 5 is -fa of what number j 88 FRACTIONS. 9. If ^ of a yard of cloth costs 4 dollars, what is the cost of the whole yard ? the cost of | of a yard ? 10. If 20 gallons of water flow from a spring in \ of an hour, how many gallons flow in one hour ( in | of an hour ? in f- of an hour ? 11. If -J- of an ounce of the otto of roses costs 5 guineas, what is the cost of 1 ounce ? of | of an ounce ? of -^- of an ounce ? 12. If one pound of sugar costs 30 cents, what part of a pound can be bought for 2 cents ? for 3 cents ? 5 cents ? 6 cents ? 10 cents ? 15 cents ? 13. If one yard of ribbon costs 40 cents, what part of a yard costs 10 cents ? 4 cents ? 8 cents \ 20 cents ? 5 cents ? 1 cent ? 2 cents ? 14. A minute contains 120 half seconds, what part of a minute do 12 half seconds make ? 10 half seconds ? 6 half seconds? 15 half seconds? 8 half seconds? 20 half seconds? 40 half seconds? 30 half seconds? 60 half seconds ? 1 half second ? 2 half seconds ? 3 half seconds ? 15. A whole hive of bees yield 36 pounds of honey in one year, what part of the hive yields 6 pounds ? 9 pounds ? 12 pounds ? 4 pounds ? 2 pounds ? 18 pounds ? 16. How long will it take a vessel which sails 10 miles an hour, to sail 67 miles ? 45 miles? 102 miles? 507 miles? 422 miles? 53 miles? 17. At 9 dollars a barrel, how many barrels of flour can be bought for 28 dollars ? 39 dollars \ 69 dollars ? 71 dollars ? 18. If corn costs 5 dollars a barrel, how much can be bought for 47 dollars? 54 dollars? 61 dollars? 23 FRACTIONS. 89 LESSON V. 1. If 5 bushels of wheat cost 9 dollars, what is the cost of 10 bushels ? PROCESS. 10 bushels is 2 times 5 bushels, hence cysts twice as much, or 18 dollars. 2. If 12 bushels of wheat cost 20 dollars, what is the cost of 3 bushels ? 4 bushels ? G bushels ? 2 bushels? 1 bushel? PROCESS. 3 bushels is ^ of 12 bushels, and costs erefore ^ of 20 dollars, or 5 dollars. 3. How many dozen in 10T ? 112 ? 145 ? 26 ? 4. 4 men can do a piece of work in 45 days,- in how many days can 12 men do the same work ? 20 men ? 40 men ? 30 men ? 60 men ? 32 men ? 28 len? 5.. If each yard of a certain cloth cost 2^ dollars, what is the cost of 5 yards ? Twice 5 and 1 fifth of 5 are how much ? 6. If a man travels 7 miles an hour, how far does he travel in 1^- hour? in 4 and f hours? in 6| hours ? 8 f- hours ? 7. How much is 3 times 10 and -^ of 10 ? 5 times 10 and -& of 10 ? 8 times 10 and -& of 10 ? 10 times 10 and T 8 oflO? 8. How much is 9 times 8 and -| of 8 ? 10 times 8 and | of 8 ? 7 times 8 and f of 8 ? 9. At 2 dollars a bushel, what will be the cost of \\ bushel of wheat? 5 bushels? 100 bushels? 25 bushels ? 10. A boy gave away 7 apples, which was -J of the number of apples which he had ; how many apples had he ? 11. Frank is 10 years old and is -J- as old as his father, how old is his father ? 12. If | of an acre of land costs 25 dollars, what is 90 FRACTIONS. the cost of -|- of the acre ? Of the whole acre ? Of -f- of the acre ? 13. If T 9 of a gallon of water leaks from a vessel in 27 hours, in how many hours will -fa of a gallon leak out.? In how many hours will one gallon leak out ? -fa of a gallon ? -^f of a gallon ? 14. Two boats are moving in the same direction ; one gains on the other % of a mile in 35 minutes ; in how many minutes does it gain -J- of a mile ? 1 mile ? f of a mile ? 15. A merchant gains ^ of a dollar in each sale of 8 dollars ; what sales must he make in order to gain -J- of a dollar ? 1 dollar ? of a dollar \ 16. 8 is |^ of what number? Is -J of what number? -ig 9 - of what number ? ^ of what number ? f of what number ? |- of what number? PROCESS. If 8 is - of the number, then ^ of 8, or 2, is ^ of the number. If \ of the number is %,%of it, or the entire number, is 6 times 2, or 12. 17. 3 is f of what number? Is f of what number? if- of what number ? 18. 8 is f of what number? of what number? -^ of what number? T \- of what number? yf^j- of what number ? -^ of what number ? -| of what num- ber ? 19. 12 is f of what number? -| of what number? -ff of what number? |f of what number? -j^- of what number ? 20. 9 is f of what number? |- of what number? -^ of what number ? T 9 g- of what number ? -| of what number ? ^ of what number ? FRACTIONS. 91 LESSON VI. lV IjJT A "A T 6 TV TIT A A 1. If a line be divided into two equal parts, and of these parts be divided into two equal parts. 92 FRACTIONS. into how many equal parts will the line be divided ? One half is equal to how many fourths ? 2. If a line be divided into two equal parts, and each of these parts into three equal parts, what part of the whole line will each of those parts be ? One half is equal to how many sixths ? 3. If we divide each half of the line into 4 equal parts, how many of these parts will the whole line con- tain ? % is equal to how many eighths ? ^ is equal to how many tenths ? 4. In what fractions can halves be expressed ? ANS. In fourths, sixths, eighths, tenths, cfe., whose denominators are multiples of 2. 5. If a line be divided into three equal parts, and each of these parts successively into 2, 3, 4, 5, &c., equal parts, what part of the line will each of these parts be respectively ? 6. How many sixths, ninths, twelfths, fifteenths, twentieths ? 7. In what equivalent fractions can thirds be ex- pressed ? ANS. In sixths, ninths, twelfths, &c., whose denomi- nators are multiples of 3. 8. If a line be divided into 4 equal parts, and each of these parts into 2 equal parts, in how many parts will the line be divided ? % is equal to how many eighths ? How many sixteenths ? How many twelfths ? 9. One fifth is how many tenths ? How many twentieths ? How many fifteenths. 10. One sixth is how many twelfths ? How many eighteenths ? How many twenty-fourths ? 11. What are the denominators of equivalent frac- tions in which fourths may be expressed ? 12. What are the denominators of equivalent frac- tions in which fifths may be expressed ? 13. What are the denominators of equivalent frac- tions in which sixths may be expressed ? FRACTIONS. 93 14. Express in parts of a unit 3 times as small. In parts 5 times as small. 10 times as small. In parts 100 times as small. 15. Express f in parts 5 times as small. Find four fractions, each of which is equal to f . f is equal to how many forty-fourths? 16. How many parts of a unit, 10 times as small, is % equal to ? How many parts of a unit 10 times as small is ^ equal to ? Find 5 fractions, each equal to f . f is equal to how many sixtieths ? 17. Find 10 fractions, each of which is equal to f. How many parts of a unit 15 times as small is -J- equal to ? Is f "equal to ? Find 6 fractions, each of which is equal to -| . 18. 1 = = ^ = ^ = \ = \= \ === T^ = -gV = 1 _ 2 __ _ JLQ.Q. 4 Q n - ft o 0' T ~ ! (Read 1 = how many halves, &c., &c. ? 1=2 what? 3 what? &c.) 1 Q Q ! ? _ ! f _ 12. 16. JJ fifi. 1J. ^ -g- 3- -j-g- TO"0~~ I ? ' 90 q ? _ t -I & 12 4i ^U. O = -3 T7 T Q- -3-^- , - 21. What multiples must the denominators of frac- tions be in which sevenths can be expressed ? In which eighths can be expressed ? In which ninths can be expressed ? In which tenths can be expressed ? 22. Give 5 fractions, equal to \. Give 5 equal to |. Give 5 fractions equal to . Give 5 equal to T V 23. Express f in parts 4 times as small. Express f in parts 6 times as small. T 9 F is equal to how many twentieths ? how many fiftieths ? how many hun- dredths ? how many two hundredths ? | is how many forty-eighths ? 24. To change fifths into tenths, into how many equal parts must each fifth be divided ? To change fifths into fifteenths, into how many ? into twentieths, into how many ? into thirtieths, into how many must each be divided ? 94 FRACTIONS. 25. T f- are how many forty-eighths ? how many sixty-fourths ? how many ninety-sixths ? 26. Change f, y^, y 7 -^, and -J-J-, each to thirtieths. 27. Change f, f, If, and ^ each to ninetieths. 28. Change f , f , f , and f to tenths. 29. Change y^ to three-hundredths. Change T 5 to thirty-ninths. Change -J to ninety-sixths. 30. How many 72ds in f ? f? f ? f? 1? -U-? fl? H *** 31. How many IGOths in ? f ? ? f ? 32. How many lOOths of a dollar make y 1 ^ of a dol- lar ? How many half a dollar ? 33. How do you find a fraction of a greater denom- inator equal to a given fraction ? LESSON VII. 1. A line is divided into 10 equal parts; what part of the line will T 5 ^ make ? If a line is divided into 12 equal parts, what part will T 6 ^- make ? 2. Reduce A; *5 A; i ; WV; W; to halves. What must be done in order to bring T 6 ^- back to -J- ? 3. Change ^ to fifths. Change |-f- to fifths. Change -^ to halves. Change |-|- to thirds ; also to fourths. 4. T 8 2- of a bushel is how many sixths of a bushel ? How many thirds of a bushel ? 5. Express ^- in parts of a unit twice as great. Express it in parts of a unit 5 times as great. Ex- press it in parts of a unit 10 times as great. 6. |-f is equal to what fraction with a denominator half as" great ? One-third as great ? as great ? -J- as great 2 -|- as great ? T ^- as great ? -g^ as great ( 7. How do you change a fraction into an equal fraction of smaller denominator ? In order to express a fraction in parts 3 times as great, the numerator and FRACTIONS. 95 denominator must be divisible by what ? In parts 4 times as great, divisible by what ? In parts 6 times as great ? 8. Can -f-, f, f 3 f, |, TV b e expressed exactly in greater parts of a unit ? Can they be expressed in smaller parts of a unit ? 9. ^ = f = |- = 1-g-g-, &c. |- is said to be in lower terms than any of its equivalent fractions, being ex- pressed in smaller figures. In the same manner -f- is a fraction at its lowest terms, or simplest form. 10. When is a fraction in its simplest form ? ANS. When its numerator and denominator have no common divisor greater than 1. 11. Reduce f f to its simplest form. 12. Reduce -J-f to its simplest form. 13. Reduce f|- and y 2 ^ each to its simplest form. 14. Reduce -f|- to its simplest form. 15. Reduce |f to its simplest form. 16. Reduce -f/-^ to its simplest form. 17. How do you reduce a fraction to its simplest form ? 18. If you multiply the denominator of the fraction f by 4, what change do you make in the value of the fraction \ If you multiply the numerator of the frac- tion f by 4, what change do you make in the value? 19. If you multiply both the numerator and de- nominator of f by 4, the fraction | * | = = | ; why ? ANS. Because we take 4 times as many parts , each of which is one fourth as great. 20. If you divide the denominator of the fraction T 8 j by 4, what change of value do you make in the frac- tion ? If you divide the numerator by 4 what change do you make ? If you divide both numerator and de- nominator by 4 you make no change ; why ? ANS. Because you take one fourth as many parts, each of which is 4 times as great. NOTE. The teacluT should ilhr^trato this with other examples until it is perfectly clear to each punil. 96 FRACTIONS. 21. How many 9ths in -|| ? How many 7ths in 22. How many 8ths in f ? In f f ? 23. Eeduce to the lowest terms the following frac- 3ns : tions : A? *- i. VJ 1 T V-> lower terms, 24. Give tive fractions which cannot be reduced to >wer terms. LESSON VIII. 1. How do you express % and -J- by two other fractions having tKe same denominator how do you proceed ? ANS. f $ = | = T V and i 2 16. What is the least common denominator of -|-, T ^-, and -^ ? Reduce to common denominators 17. f and f. 20. T V and -^. 18. f andf 21. 1 and ^ 19. f and f. 22. ||- and ^. 23. Reduce to the least common denominator % and T V 24. Reduce to the least common denominator y 1 ^ and ^-. 25. Reduce to the least common denominator ? T 3 , and -J-. 26. Reduce to the least common denominator , 5 27. Reduce ^, -j^, and ^ to the least common de- nominator. 28. Reduce , f , f, |, -j^- and ||- to the least coin- >n denominator. 29. How do you reduce fractions to common de- minators ? 30. How do you reduce fractions to the least com- 7 98 FRACTIONS. mon denominators, when the denominators have no common factor? 31. How do yon find the least common denominator, when, the denominators have a common factor ? LESSON IX. 1. A boy gave his brother ^ of an apple, and his sister of an apple ; how many fourths did he give to both? 2. A man sold a bushel of apples for -| of a dollar, a bushel of potatoes for | of a dollar, and a bushel of meal for -| of a dollar. How many dollars did he re- ceive for all ? 3. A farmer divided his land into several lots. One lot contained | of an acre, a second lot ^ of an acre, a third lot -f- of an acre, and a fourth lot if- of an acre. How many acres in all the lots ? 4. One man pays me 8| dollars, and another pays me 1-J- dollar ; how much do both together pay me ? 5. | and f are how much? $ + f ? J / + * ? T 9 o 7. A workman receives from his employer at dif- ferent times if of a dollar, 4^- of a dollar, 3^ of a dollar, 11 T 5 T of* a dollar, and 2y 9 ^- of a dollar. How many dollars did he receive altogether ? 8. A vintner has in his cellar 4 casks ; the first con- tains Sy 1 ^- gallons of wine, the second 7 T 6 Q-, the third f-^, and the fourth 5^ gallons ; how many gallons of wine in the four casks \ 9. f-f 1 L = ? Can these be added without changing them first into the same denomination ? PROCESS. J f ; | ; + |=f.+_f = |. 10. How do you add fractions having a common FRACTIONS. 99 demominator? Plow do you add fractions of different denominators? 11. i+|- f+t 13. . PROCESS. 1|- i'T V? 5. What is meant by multiplying 5 by ^-? ANS. To take ^ of 5. 6. If a number be multiplied by a number less than unity, is the product greater or less than the first number ? Multiply 5 by f-. 7. How much is 10 times f ? f xlO? f of 10? How much is 32 times f? |x32? f of 32? How much is 23 times f ? f x 23 ? f of 23 ? 8. How do you find a given fraction of any number ? 9. A man sold 10 yards of cloth at 2-J- dollars a yard ; what did he receive for the 10 yards ? 10. At 2 dollars a yard, what will 3-J- yards of cloth cost? 11. At 5 dollars a barrel, what will 4 barrels of flour cost? 12. If a man walks 5 miles an hour, how far will he walk in 6|- hours ? > 13. How much is 5 x 6|? 6 x 7-J? 6f x 6? 9f X 62 4^x3? 1^x4? 5x4A 31^x10? x 9? 91|x 8? 20f x Y? 14. How much is 12 times 10 and T % of 10? 15. How much is 9 times 7 and of 7? 102 FRACTIONS. 16. 10X T V= ? ^Xl0=? -^oflO ? 11 X ? Wxl2? 17. How much do you get when you multiply i by 1 ? 18. How much do you get when you multiply -J- by ^ ? How much is -J- x \ ? ANS. % of \. 19. If you take a line and divide it into 3 equal parts, and take ^ of one of these parts, what part of the whole line do you take ? If you divide the line into two equal parts, and take -J- of one of these parts, what part of the whole line do you take? i x |- = % of -J- = -J- of |-. Show this by a line on your slate. * TT === T7T X y-Q- = . 21. f multiplied by f is 2 times -J- x J = ? How much is I- off? Off? Of-jV? Of^? Of||? PROCESS. -J x f, o/ 1 -^ of ^ is 3 x ^ ^/"^- = ^C-. 22. How much is I- of --? |of|? fof|? How much is | of ^ ? -J-off? j-off? | of *f ? of |? 23. How much is | xf ? fx | = f of f fof f ? How much is -f x f ? -f- x -^ ? yV x iV - I x I 4 X 3 ? | X | ? | X 3 ? ^ x , f| f>< 7 ? 24. How much is -f- x | ? ^ of f ? f of | ? ^ 25. A man sold a -bushel of wheat for 1 dollars. What is the cost of -J- of the bushel ? 26. How much is 1 multiplied by J ? What does it mean to multiply 1|- by -J ? ANS. To take -i- of ^^. PROCESS. 1^ is f . % of 27. Sold a barrel of flour for 7| dollars. What was the cost of -- of the barrel ? FRACTIONS. 103 28. How much is 8$ x | = | of 8 ? How much is 2 x i? 9i x f? 3 x | ? 4f x f ? If x 3 T V? fx3f? JxlOi? 29. What is the cost of 3 yards of cloth at 1% dol- lar a yard? How much is 3 x 1J? SOLUTION. 3 x 1 =\ 3 - x f = f of *- ^- or 4f 30. How much is If x 1? 1J x 2f ? 2f x 7J-? 2fxl? 6fx2 T V? Hx6f? 2|x3? 1 31. Find the sum, difference, and product of f and -J. Of 1| and 2. Of 2J- and 3f . Of 1 and 2f Of 7| and 3f 32. How do you multiply a fraction by a whole number ? How do you multiply a fraction by a frac- tion, or take a part or parts of a fraction ? How do you multiply a mixed number by a mixed number ? 33. A man bought a ton of coal for 17f dollars a ton. What was the cost of -J- of a ton ? 34 A man bought 10 bushels of wheat for 27| dol- lars. What did he pay for each bushel ? 35. 5 yards of cloth cost 18f dollars. What is the cost of one yard 2 LESSON XII. 1. If an apple is divided into two equal parts, each part is ^. 1 divided by 2 = ? If 2 apples each be divided into 3 equal parts and ^ part of each be taken, we will .have f of an apple. 2 divided by 3 what ? 2. What do we mean by dividing 1 by 2 ? 2 by 3 ? ANS. To divide 1 into two equal parts and take one of them, which gives ^. In the same manner to divide 2 ly 3 gives f . 3. What fraction is equal to 1 divided by 5 ? l-~6 ? 7? i^s? 1-^-9? 4. If you divide half an orange into two equal parts, what part of the orange do you get ? divided by 2 is what ? . 104 FRACTIONS. 5. How much is divided by 3 ? 4 ? 5 ? 6 ? 7 ? 8 ? 9 ? 10 ? ANS. J- divided l>y 3 is ^ of -J-, or -|-, cfee. 6. How much is divided by 3? 4? 5? How much is f divided by 3? 4 ? 5 ? 6? 7? 8? 7. A man had |- of a barrel of flour, and divided it equally among 6 persons. How much did he give to each ? How much is ^^6 = -J- of ? 8. A person wished to divide f of an acre of land into 10 equal lots ? How much land would each lot contain ? 9. Divide by 9. By 2. By 5. By 7. By 6. Divide | by 11. J by 5. fl by 4. ff by 5. 10. How many halves make 1 ? How often is % contained in one ? How many halves in 2 ? How often is contained in 2 ? 11. A person wishes to distribute 4 barrels of flour so as to give ^ of a barrel to each of a number of families. How many families could he supply ? 12. How many thirds in 10 ? -J- is contained in 10 how many times ? is contained in 5, 6, 7, 8, 9, how many times ? 13. How much is 1 divided by -J- ? 2 divided by -J- ? 5 divided by -J- ? 9 divided by | ? 11 divided by -iV ? 12 divided by ^ ? 14 How much is 10 divided by ^ ? f is contained in 10 how many times ? SOLUTION. J- is contained in 10, 50 fo'my \ gives 45 ; hence 5 di- vided by -| must give a quotient 6 times as small = 4 / = 7f 16. How much is 6 divided by f ? 6 is f of what number ? How much is 6 divided by 5 ? 6 is 5 times what number ? How much is 10 divided by -f- ? 10 is % x by what number ? 10 is -f of what number ? FRACTIONS. 105 17. How much is 6-f-f ? 6 is f of what number ? 18. How much is 4-^-J- ? 4 is ^ of what number ? 19. How much is 16-^f ? 16 is | of what number ? 20. How much is 12-^ ? 10 -Hr ? 6 divided by | ? 9-T--& ? 5 divided by f ? 11 divided by ^ ? 21. How much is 100 divided by f ? | ? f ? ? 22. 2 is f of what number ? 5 ? 3 ? 7 ? 10 ? 11 ? 12? 15? 23. 60 is f of what number ? f of what number ? -f of what number ? T ^- of what number ? 24. How do you divide a fraction by a whole num- ber ? How do you divide a whole number by a frac- tion? 25. If one soldier's ration of flour is 1-J- pound, how many rations will 8 pounds of flour make ? 1^- is con- tained how often in 8 ? SOLUTION. 1-J- is |-, and 8-f-f is 6. 26. How often is 6f contained in 9 ? How much is 60 divided by 3|-? By 1-JJ 3f ? How much is 2 divided by 3^ ? 4^ ? How much is 5 divided by 4 ? ^27. How much is 2f + 2 ? 8f -f- 7 ? 14f -f- 12 ? 28. If f of a ton of coal is burned in a stove in one month, how long will f of a ton last for the same stove? f is contained how often in f ? 3 in 9 how many times ? -jf- in how many times ? -f$ in T 9 ? -A- in 6 9 ? 29. f in - 2 5 - how many times ? -^ divided by f is how much? How much is -i/- divided by f ? - 1 1 ^ contains ^ how many times? -i|-Q--f-^-= ? -^^-v- 14 = ? -^gQ-~|-g= ? J^--^.|=? . contains -| how many times ? f divided by f is how much ? 6 con- tains 5 how often ? 5 divided by 6 is how much ? 30. 1 divided by ^ is how much ? |- divided by -^ is how much ? ANS. Since 1 -=- ^ is 3, |- -f- -J ?m^ l)e ^ of 3, 0r f . 106 FRACTIONS. 31. How much is divided by -J- ? Asrs. J- = ^ . 1. In 1 scruple how many grains? in 2? in 3? in \ of a scruple ? in 2|- scruples ? 2. In 2 drams how many scruples ? in 3 ? in 4 ? in ^ of a dram ? in 2-f drams ? 126 DENOMINATE NUMBERS. t3?_4? I many 3. In 2 ounces how many drams ? in 3 ? 4 ? 2f ? 4. In y^ of a pound how many grains ? How m grains in 4 drams, 3 scruples, 5 grains ? Avoirdupois Weight. This weight is used in all ordinary weighing. The Avoirdupois pound is heavier than the Troy pound, 144 Avoirdupois pounds being equal to 175 Troy pounds. TABLE. 16 drams make 1 ounce marked oz. 16 ounces make 1 pound marked Ib. 25 pounds make 1 quarter marked qr. 4 quarters, or 100 Ibs., make 1 hundred weight marked cwt. 20 hundred weight make 1 ton, marked T. 1. In 2 pounds how many ounces ? in 3 ? in 4 ? in % of a pound ? in 2f ? 2. In 32 ounces how many pounds ? in 48? 64? 80? 82? 3. How many pounds in 2 quarters? in 3? in 4^? 4. How many quarters in 50 pounds ? 100 pounds ? 200 pounds ? 76 pounds ? 5. How many cwt. in 8 quarters ? in 16 ? in 25 ? in 33? 6. How many cwt. in 2 tons? 4 tons? \ a ton ? -fa of a ton ? in f of a ton ? in 5 tons ? What part of a ton is 1 cwt. ? 7. How many tons in 40 cwt. ? in 80 ? in 60 ? in 45 ? 8. What is the cost of 4|- cwt. of sugar, at 9 cents a pound? at 10 cents? 9. What is the cost of 5 tons of hay, at 20 dollars a ton ? 10. How much will 2 cwt. 2 qrs. of sugar cost at 10 cents a pound ? 11. Bought 3 tons and 10 cwt, of hay at 12 dollars a ton ? What was the cost of it ? DENOMINATE NUMBERS. 127 LESSON Y. United States Money. The units are coins of gold, silver, copper, and nickel, of fixed weight, size, and shape. TABLE. Gold. Gold. Nickel. Silver. Silver. 10 mills make one cent. marked c. 10 cents make 1 dime marked d. 10 dimes make 1 dollar marked $. 10 dollars make 1 eagle marked E. 1. How many mills in 2 cents? 9 cents? 2} cents? How many cents in 50 mills? 40 mills? 25 mills? 2. How many cents in 2 dimes ? in 3 ? in 4^ ? in 5|? How many dimes in 20 cents? 25 cents? 50 cents ? 75 cents ? 128 DENOMINATE NUMBERS. 3. How many dimes in 2 dollars ? 4 dollars ? dollars? 6^ dollars? How many dollars in 20 dimes"? 40 dimes? 45 dimes? 4. How many dollars in 2 eagles? in a half-eagle? in 3^ eagles? in 5J eagles? How many eagles in 20 dollars ? 35 dollars ? 42 dollars ? 5 What part of a dollar is 1 cent ? is 1 mill ? is 50 cents ? 33| cents ? 25 cents ? 20 cents ? 1 dime ? 16| cents? 12^ cents? 6. What part of an eagle is 1 djme ? 5 dimes ? 7. How many cents in |- of a dollar ? in J ? in ? in -? in |? in |? -jV? ^-? ^-? ^- of a dollar? of a dollar? 8. Bought six barrels of flour at $9.33^ cents a bar- rel ; what was the cost of the whole ? 9. Paid 6J cents a pound for 48 pounds of nails ; how many dollars did the whole cost ? 10. At 37J cents a yard, what is the cost of 6 yards of ribbon ? 11. If 6 pounds of sugar can be bought for 60 cents, how much can be bought for an eagle? 12. What is the cost of 100 articles at 1 cent each ? 2 cents? 3 cents? 12 cents? Table of English Money. 4 farthings (far.) make 1 penny marked d. 12 pence make 1 shilling marked s. .20 shillings make 1 pound marked . The coins of this table are gold, silver, and copper. A sovereign is a gold coin = 1 pound or 20 shillings. The guinea is 21 shillings. A pound is 4 dollars and 84 cents. 1. How many farthings in 2 pence ? in 3 pence ? in 6J pence ? ^ a penny ? f of a penny ? in 4f pence ? 2. How many pence in 8 farthings ? in 10 ? in 20 ? in 60? DENOMINATE NUMBEKS. 129 3. How many pence in 2 shillings ? in -J- of a shil- ling ? in \ of a shilling ? in of a shilling ? -jj- of a shilling ? in 5s. 6d. ? in 10s. 2d. ? in 10s. 6d. ? in 2s. 8 an ^ j^, respectively. The prefixes deca, hecto, kilo, METRIC SYSTEM. 133 myria, mean 10, 100, 1000, 10,000, respectively. These are used in all the tables of this system. In commerce the expressions 10 metres, 100 metres, 1000 metres, 10,000 metres, are invariably used instead of decametre, hectometre, kilometre. 1. How many millimetres in 2 centimetres ? 4 cen- timetres ? in 3^ centimetres ? What part of a centi- metre is 1 millimetre ? 2 millimetres ? How many centimetres in 50 millimetres ? in 65 millimetres ? 2. What part of a metre is a millimetre ? a centi- metre ? What part of a myriametre is a metre ? How many metres make a kilometre ? how many centi- metres ? how many decimetres ? 3. Bought 5 decimetres of ribbon at 1 dollar a metre, what was the cost ? 4. What is the cost of 30 metres of cloth at half a dollar a decimetre ? at ^ of a dollar a decimetre ? at 1 dollar a decimetre ? 5. A tower is 55 metres high ; how many centi- metres ? 6. How many miles in 100 myriametres ? 40 myria- metres ? Square Measure. The natural unit is the centiare or square metre, equal to 1-^- square yard, nearly. 100 centiares make 1 are = 100 square metres. 10 ares make 1 decare. 10 decares make 1 hectare = 2-^j- acres, 2 acres, nearly. 1. How many square metres in 15 centiares? how many square metres in 1 are ? in 1 hectare ? in 2 hectares? How many acres in 100 hectares? How many square yards in 100 square metres ? 2. What is the cost of 15 hectares of land at 5 dol- 134: METRIC SYSTEM. lars the decare? "What is the cost of 15 acres of land, at 50 dollars the hectare ? NOTE. To make the table of square measure complete, we should have the square decimetre, square centimetre, and square millimetre but these are seldom used. Cubic Measure. The unit of this table is the cubic metre = 1.3 cub. yard. This is called a stere when used in measuring wood, or hectolitre when applied to liquid or dry measure, of which the principal unit is the litre or cubic decimetre = y 9 ^ of a quart, dry measure, and 1-rtSr f a quart, liquid measure. TABLE. 10 millilitres make 1 centilitre = 10 cubic centi- metres. 10 centilitres make 1 decilitre. 10 decilitres make 1 litre = 1 cubic decimetre = -fa of a dry quart, D. M., lyf-o of a quart, L. M. 10 litres make 1 decalitre. 10 decalitres make 1 hectolitre. 10 hectolitres make 1 kilolitre or stere = 1 cubic metre. 1. What part of a kilolitre is 1 litre ? 2 litres ? 1 decilitre? 1 decalitre? 5 hectolitres? 100 decalitres? 2. How many millilitres make one decalitre ? 3. How many quarts D. M. in 10 litres? How many quarts, Liquid Measure, in 100 litres ? 4. What is the cost of 20 hectolitres of wine at 10 cents a litre ? 5. 1 hectolitre is what part of a cubic metre ? 1 decilitre is what part of a cubic decimetre? is how many cubic centimetres ? METBIC SYSTEM. 135 Weights. The principal unit is the gramme, or the weight of a millilitre of pure water when it is heaviest. The gramme is 15^^- grains Avoirdupois. TABLE. 10 milligrammes make 1 ceirtigramme. 10 centigrammes make 1 decigramme. 10 decigrammes make 1 gramme = 15-^- grains Avoirdupois. 10 grammes make 1 decagramme. 10 decagrammes make 1 hectogramme. 10 hectogrammes make one kilogramme = 2-^- Ibs. Avoirdupois. 10 kilogrammes make 1 myriagramme. 10 myriagrammes make 1 quintal. 10 quintals make 1 inillier or tonneau = ly 1 ^- ton, nearly. 1. How many kilogrammes in 1 quintal ? in 5 quin- tals ? in 4 quintals ? How many grammes in 1 ton- neau ? How many myriagrammes in 3 tonneaux ? 2. 1 milligramme is what part of two grammes ? of 3 decagrammes? 1 centigramme is what part of a kilogramme ? How many grammes in 5 kilogram- mes ? 3. What is the cost of two kilogrammes of hay at 1 dollar the quintal ? 4. At 2 dollars the kilogramme, what is the cost of a hectogramme of tobacco? of a decagramme? of 15 grammes ? 5. How many pounds Avoirdupois in 1 myria- gramme ? 6. One hundred pounds how many kilogrammes ? One hundred kilogrammes how many pounds ? 136 TABLE OF FRENCH MONEY. 7. What are some of the advantages of the metric system of weights and measures ? TABLE OF FRENCH MONEY. 10 millimes make 1 centime. 100 centimes make 1 franc = 19 cents ,,3 mills, U. S. money. 20 francs make 1 louis. 1. 5 centimes make 1 sou. The franc is how many sous ? 5 francs are nearly one dollar. 2. A franc in silver weighs 5 grammes. 40 five- franc pieces in silver weigh one kilogramme. 3. What is the weight of 1000 silver francs? 4. What is the value of a sum of money weighing two kilogrammes ? 5. What is the weight of a litre of pure water when it is heaviest ? of a decilitre ? of a decalitre ? 6. Bought 500 kilogrammes of hay at 1 dollar the quintal ; how much did it cost ? 7. A garden of 500 square metres is sold for $50 ; how much is that for each are ? 8. A staircase of 12 steps descends into a cellar 2 metres and 76 centimetres deep j what is the height of each step ? PERCENTAGE. 137 CHAPTER X. PERCENTAGE. LESSON I. Per cent, is a contraction for per centum, which means by the hundred, for each hundred, or in a hun- dred. Thus 5 per cent, of any number means 5 parts in every hundred parts of the number, or 5 hundredths of ?he number. To take 6 per cent, of a number is to take 6 hundredths of the number, or 6 times 1 per cent., or 6 times 1 hundredth of the number. The 5 and 6 in 5 per cent, and 6 per cent, are called the rates per cent. 5 per cent, and 6 per cent, are merely other forms for the fractions y^ and T -| . 1. "What is meant by per cent. \ What is, then, 5 per cent, of any number \ What is meant by the rate per cent. ? 2. How much is 1 per cent, of 40 ? 50 ? 60 ? 4 ? 5 ? 6 ? 3. How much is 1 per cent, of 20 ? 2 per cent, of 20 ? 3 per cent. ? 5 per cent. ? 4 per cent. ? -J of 1 per cent. ? J of 1 per cent. ? 2|- per cent. ? 10 per cent. ? PROCESS. 1 per cent, of 20 is y-^- of 20 = -gfa = \ ; | 0/* 1 jp^/ 1 ?^. i ^ of ^ or T L- ; 4 jp^r cent, of 20 is 4 x -J-, 6>r |- ; 10 jt?^ tf^rf. is 10 x -J- = 2. 4. How much is 10 per cent, of 540 ? 320 ? 250 ? 100 ? How much is 20 per cent, of the same num- bers? 5. How much is 100 per cent, of 5 ? of 6 ? of any number? How much is 200 per cent, of 8? 40 ? of any number? 6. Every per cent, fraction has what for numerator and what for denominator ? 138 PERCENTAGE. ANS. The rate per cent, for the numerator, and one hundred for the denominator. 7. Which per cent, fractions, or wliicli hundredths, can be most readily reduced to simpler fractions ? ANS. Those whose numerators are divisors of 100. 8. What fraction of a number having 1 for its nu- merator is 2 per cent, of the number ? PROCESS. 2 per cent, of a number is y-f-g- of the num- ~ber, yf Q- in its simplest form = -^. 9. What is the simplest form of 4 per cent. ? 5 per cent.? 10 per cent.? 20 per cent.? 25 per cent.? 50 per cent. ? 75 per cent. ? 10. What per cent, of a number is |- of the number ? |- is how many hundredths ? 11. What per cent, of a number is ^ of it? -J- of it ? TV of it? jV of it? ^ of it? T V of it? T^T of it? ^ of it? of it ? yV of it ? y^ of it ? 12. Which fractions can be extended most easily to hundredths ? ANS. Those of whose denominators 100 is a mul- tiple. 13. i of a number is what per cent, of the number ? Extend ^ to hundredths. PROCESS. 100-^-3 is 33^, hence % is -f- f^ ; -|- 6/*# n^ra- Z>r is |-|^ ? 6>r 33|- jpr cent, of it. 11. What per cent, of a number is -J- of it ? |- of it? T Vofit? T Vofit? f of it? | of it? -Jofit? f? -f- ? 15. What fraction of a number is 33^- per cent, of the number? 16f per cent, of it? 12^ per cent, of it? 8^ per cent, of it ? 6^ per cent, of it ? 66f per cent. ? 87| per cent. ? 60 per cent. ? 80 per cent. ? 90 per cent. ? 16. What part of 100 is 16f? 12J? 66f ? 6J ? 60? 80? 37? 90? 17. 5 is what per cent, of 60 ? PROCESS. 5 is T ^- o/* 60, 6r y the tens, and add to it the square of the units. Thus, to square 46, add 6 to 46, giving 52. Multiply 52 l>y 4 tens or 40, giving 2080, and to this add 36. 11. What is the square of 13? of 14 ? of 15 ? 16 ? IT? 18? 19? 12. What is the square of 20 ? of 30 ? of 40 ? of 90 ? 13. Find the square of 31; of 37; of 52; of 56 ; 27. In all the preceding chapters of miscellaneous questions the pupil should be required to frame several questions of each sort presented, and the teacher should add questions in each recitation. 160 NUMERATION AND NOTATION. CHAPTER XII. ELEMENTARY LESSOXS IN WRITTEN ARITHMETIC. LESSON I. Numeration and Notation. 1. IN the preceding chapters the pupil has learned orally the numeration and notation of numbers as high as thousands. The numbers from one to one thousand form a class of three orders of numbers. The first order is units; second, tens of units; and third, hundreds of units. In the same manner there are three orders of the class thousands: first, thou- sands ; second, tens of thousands third, hundreds of thousands. As to ten hundred we gave a new name, thousand so to ten hundred thousand it is conve- nient to give a new name, and thus form a third class. This we call a 'million. 2. We have also learned in a former chapter how to express numbers as high as thousands by means of the nine Arabic or Indian figures, together with the symbol of place, 0. These nine figures are called sig- nificant figures^ and is called a cipher, or naught, or zero. We have learned that a figure, as 7, standing by itself expresses 7 simple units ; that a or another figure placed to the right of it, thus, 70 or 72, makes it express seven tens, that is, seven units of the next higher order; that two O's, or two figures, or a cipher and a significant figure, placed to the right of it, as 700, 708, 718, or 780, make it express seven units of NUMERATION AND NOTATION. 161 the next higher order, or seven hundreds ; and that three significant figures or ciphers placed to the right of it cause the seven to express seven thousands. 3. The law here is, that each additional figure to the right of a figure increases tenfold the value of the original figure. We can now extend this law to all. higher numbers. To make the figure 7 express seven tens of thousands, we annex four figures to it ; to make it express seven hundreds of thousands, we annex five figures ; to make it express seven millions, we annex six figures. If a number is expressed in seven figures, the first figure on the right expresses units, the next tens, the next hundreds, the next thousands, the next tens of thousands, and so on to millions. That is, moving a figure one place to the left, makes its value ten times as great as before. Table. PI c3 00 g ^ s w 2 o o . -3 1 | "o 1 CO CO 3 s r3 d ce d n o 3 ^ M H EH PH I, 3 3 5, 6 2 9 o, 1 4, 9 2, 6 to 7 4 4 1 (2' 6 2 (3) (4) (1) iri read, One thousand three hundred and seventy- four. 162 NUMERATION AND NOTATION. (2) is read, Thirty-five thousand six hundred and forty-one. (3) is read, Two hundred and ninety thousand one hundred and sixty-two. (4) is read, Four million nine hundred and two thousand six hundred. 4. The is put in the place of any order of units which is wanting in the number to be expressed. Thus five thousand and six has no tens nor hundreds. Hence it is written 5006, because in order that 5 may express five thousand, it must have three figures after it, and as we have only one significant figure to write, we therefore use two O's. NOTE. When the number of tens is more than 1, we use the ter- mination -ty. 74 is seven- ty-four, instead of seven-ten s-and-four. Twenty, thirty, forty, fifty, are slightly changed from twain-ty, three-ty, four-ty, five-ty. In 62,354, instead of saying six-tens-and-two thou- sand three hundred five-tens-and-four, we say sixty-two thousand three hundred and fifty-four. 5. EXERCISES. Let the pupil read, or write in words, the following numbers : 1. 684, 596, 4000, 24000, 1000, 1001, 1021. 2. 50, 500, 5000, 50000, 50500, 50505. 3. 403, 430, 4308, 4764, 40764. 4. 10000, 10094, 10904, 10094. 5. 60, 604, 1604, 21604, 421640. 6. 123, 321, 312, 444, 4444, 44444, 444444. 7. 2000, 20000, 200200, 2200200, 2220202. Express in figures the following numbers : 1. Six hundred; six hundred and forty; six hun- dred and forty-six. 2. Four hundred and four ; four hundred and four- teen ; four hundred and forty. v 3. Three hundred and thirty ; three thousand ; three thousand and three hundred. ADDITION. 163 4. Six thousand; six thousand four hundred and forty ; six thousand four hundred and four. 5. Nine hundred and one ; one hundred and nine ; one hundred and ninety. 6. Eight hundred ; eight Hundred thousand ; eight hundred thousand four nundred and fifty ; four hun- dred and fifty-five. 7. One thousand ; one million ; six million ; six million six thousand and six hundred ; six million six hundred and fifty-four thousand three hundred and twelve. LESSON II. Addition. 6. By ADDITION we unite two or more numbers in one number. The result of the addition is called the SUM or AMOUNT. In adding large numbers, we add the units, the tens, the hundreds, &c., separately. Two cases occur. 7. I. When the sum of each column is not more than 9. EXAMPLE 1. Add 641, 132, 213. Operation. 641 132 213 986 We write the numbers so that units are in the same column, tens in the same column, hundreds in the same column. Beginning with units, we add : 3 and 2 and 1 are 6.; 1 and 3 and 4 are 8 ; 2 and 1 and 6 are 9. The sum is 986. 164: ADDITION. Add the following numbers : 2. 234 2222 3333 2000 5001 4210 312 3132 2141 1423 2111 1434 421 2321 2203 1004 422 1244 22 2314 1221 4352 1241 3101 3. What is the sum of 3241, 1320, 2103, 1025 ? 4. Add together 2345, 1201, 4321, 1102. 5. Add together 1234, 4321, 2222, 2222. 6. A man bought a house for 2300 dollars, a horse for 250 dollars, and a wagon for 120 dollars; what did he pay for them all ? 8. II. When the amount in any column is more than 9. EXAMPLE. If a merchant has 1276 dollars in bank bills, 479 dollars in gold, 784 dollars in silver, and 4 dollars in cents, how much money has he in all ? Operation. 1276 479 784 4 2543 We write, as before, units under units, tens under tens, &c. 4, 4, 9 and 6 units are 23 units, or 2 tens and 3 units. We write 3 units tinder units, and add the 2 tens with the column of tens, thus : 2, 8, 7 and 7 are 24 tens, or 2 hundreds and 4 tens. Writing 4 tens under tens, we add 2 hundreds with the column of hundreds : 2, 7, 4 and 2 are 15 (hundred). We write 5 under hundreds, and add 1 with thousands : 1 and 1 are 2. The sum is 2543. The merchant has 2543 dollars. ADDITION. 165 EXAMPLES. 1. 2704 4623 66 704 358 48502 598 749 8506 4854 79508 1942 8515 9402 987 706 749 15652 56708 74749 2.490 777 333 888 888 123 244 444 330 22 99 221 130 999 444 3 11 456 355 442 440 44 2 654 240 111 505 555 33 789 166 222 606 6 590 978 3. 8649 9876 5436 6 6789 5842 5432 4563 66 9876 3876 1234 3654 6836 7890 9204 5678 5463 6956 9876 7587 1875 6345 6796 1234 4. How many are 902010 + 178393 + 643421 + 366780 + 703020 + 683463 + 604050 + 221894? 5. What is the sum of forty-four thousand three hundred and twelve ; six thousand eight hundred and twenty-seven ; nine hundred and fifty -.two ; thirty thousand and thirty ? 6. Find the sum of ninety ; eighty thousand seven hundred and one ; two thousand seven hundred and fifty-four; one thousand five hundred and seventy; forty-two thousand and four. 7. In a nursery of trees there are 1250 apple trees, 2050 pear trees, 3500 peach trees, 1750 plum trees, 850 apricot trees; how many trees in all? 166 SUBTRACTION. LESSON III. Subtraction. 9. By SUBTRACTION we find the difference of two numbers, by taking the less number from the greater. The greater number is the MINUEND. The less number is the SUBTRAHEND. The difference is also called the REMAINDER. To subtract, we place the subtrahend under the minuend ; units under units, tens under tens, &c. Two cases may arise. 10, I. Each figure in the subtrahend may be less than the figure above it in the minuend. EXAMPLE 1. From 576 subtract 324. Operation. 576 252 Subtracting each figure in the subtrahend from the figure above it, beginning with units, we have 4 from 6, 2 ; 2 from 7, 5 ; 3 from 5, 2. The remainder is 252. PROOF. Add the units, tens, &c. of the subtrahend and remainder 2 and 4 are 6; 5 and 2 are 7; 2 and 3 are 5 and we have the minuend, 576. EXAMPLES. 2. From 540 take 200. From 860 take 300. 3. 800 5000 60000 9000 790 80000 200 2000 20000 3000 400 3000 4. 8760 9630 6320 5670 4810 5945 3000 7000 2000 3000 1000 3000 SUBTRACTION. 167 5. 937 877 697 867 633 857 6848 122 352 245 423 121 307 3007 6. 85674 4789 62476 34897 1352 3254 231 12244 11. II. One or more figures in the subtrahend may be greater than the figures above them in the minu- end. EXAMPLE. From 468 take 349. Operation. 10 468 349 119 Write the less number under the greater. As we cannot take 9 units from 8 units, we mentally add 10 to 8, and then say, 9 from 18 leaves 9, which 'we write down. Since we added 10 to the minuend, we add 1 ten, to the 4 tens of the subtrahend, and say 5 from 6 leaves 1, which we write down. Finally, 3 hundred from four hundred leaves 1 hundred. 119 is the dif- ference between the numbers, because we have taken all the parts of the less from the greater, and we have balanced the ten added to the greater by adding ten to the less. EXAMPLE. From 9434 take 3537. Operation. 101010 9434 3537 5897 168 SUBTRACTION. We say, 7 from 14, 7 ; 4 from 13, 9 ; G from 14, 8 ; 4 from 9, 5. The remainder is 5897. If there are fewer figures in the lower line than in the upper, proceed as if O's were written on the left of the lower number until the number of figures is the same in both. 732 13 807 718 8403 2390 EXAMPLES. 10 1. 670 860 490 540 650 880 25 43 38 26 39 32 10 10 2. 7860 1780 2690 806 709 243 437 272 243 333 10 3. 6072 7043 4068 5037 2342 2520 3660 1717 10 10 101010- 4. 4372 782 965 585 7184 4360 7343 2657 355 428 247 6526 3608 6740 1715 5. 2814 375 5006 4176 7583 8064 1033 185 2818 3648- 3065 3975 6. 6004 60010 10000 8200102 815240 3716 528 3196 4866769 379468 7. 7802008 10000000 951315 9555555 3357564 1 947688 2888889 MULTIPLICATION. 169 8. How much smaller is 38567 than 60600 ? 9. How much is 4009000 less 5678 ? 10. How much greater is 700000 than 599328 ? 11. Take from 43518 the number 7253, and from the remainder 7253, and so on, and give the remainder after the sixth subtraction. 12. How much is 3820 + 16488 + 347 + 5688 + 2433 - 31210? 13. A man owns a farm which cost him 5500 dol- lars ; he has paid 2875 dollars ; how much more has he to pay. 14. A merchant sold for 2825 dollars goods which cost 2138 dollars ; how much did he gain ? 15. A man bought a house and lot for 2750 dollars, and sold it for 3125 dollars ; how much did he gain ? 16. How old would a man be in 1868 who was born in 1839? LESSON IV. Jfuttiplicat ion. 12. If a man can earn 8 dollars in one week, in 4 weeks he can earn 4 times 8 dollars, or 32 dollars. This is multiplication: 8, the number to be re- peated, is called the MULTIPLICAND : 4, which shows how many times the multiplicand is to be taken, is called the MULTIPLIER, and 32, the result of the multi- plication, is the PRODUCT. In multiplying large numbers, there are two cases : 13. I. When the multiplier is a single figure. EXAMPLE 1. Multiply 467 by 5. Operation. 467 5 2335 170 MULTIPLICATION. . We write the multiplier under the multiplicand, units under units, and say, 5 times 7 units are 35 units, or three tens and 5 units. We write 5 units below, and reserve 3 tens. 5 times 6 tens are 30 tens, which with 3 tens make 33 tens, or 3 hundreds and 3 tens. Writing 3 tens in tens' place, we reserve 3 hundred. 5 times 4 hundred are 20 hundred, which with 3 hundred mate 23 hundred. This we write down, and have for the product, 2335. 2. 356 825 6745 4567 Multiplicand. 4536 Multiplier. 1424 27402 Product. 3. 8474 9876 5432 12345 2789 4. Multiply 4825 by 2; by 3 ; by 4; by 5 ; by 6. 5. Multiply 3775 by 5 ; by 6 ; by 7 ; by 8 ; by 9. 6. Multiply 5709 by 4; 'by 5; by 6; by 7; by 8; by 9. 7. If one horse costs 275 dollars, what is the cost of 8 horses ? 8. If one house is worth 3275 dollars, what is the value of 7 similar houses ? 9. If the multiplicand is 3917 and the multiplier is 6, what is the product? 10. Multiply the sum of 1847 and 2043 by 8. 11. Multiply the difference between 3194 and 1536 by 9. 14. II. When the multiplier contains more than one figure. EXAMPLE 1. Multiply 843 by 26. MULTIPLICATION. 171 Operation,, 843 26 5058 1686 21918 Write the multiplier under the multiplicand, units under units, tens under tens, &c. Multiply by 6, the units figure, as in Case I. In multiplying by 2 tens, place the first figure of this product under 2, the multiplier. For, 2 tens times 3 are 6 tens; therefore, the 6 should be in the second, or tens', place. Add the two partial products, and find the entire product, 21918. EXAMPLE 2. Multiply 4357 by 345. Operation. 4357 345 21785 17428 13071 1503165 7 _ 35 ; write 5 and " carry" 3. = 25, + 3 28 ; write 8. = 15, + 2 = 17 ; write 7. = 20, + 1 = 21 ; write 21. 7 = 28 ; write 8 under 4. 5 = 20, + 2 22 ; write 2. 3 _ 12, + 2 = 14 ; write 4. 4 = 16, + 1 17 ; write 17. 1 72 MULTIPLICATION. 3 x 7 = 21 ; write 1 under 3. 3 x 5 = 15, + 2 = 17 ; write 7. 3x3 = 9, + 1 = 10; write 0. 3 x 4 12, + 1 13 ; write 13. The sum of the partial products is the entire pro- duct, 1,503,165. 3. 3458 8431 1357 2465 5438 24 35 54 89 146 4. 5417 5104 3547 . 1596 2705 123 456 258 357 403 5. Multiply 1047 by 284; by 207; by 615. 6. Multiply 3579 by 123 ; by 612 ; by 246. 7. Multiply 4680 by 340 ; by 360 ; by 801. 8. Multiply 6143 by 200; by 4200. 6143 6143 200 4200 1228600 1228600 24572 25800600 9. Multiply 3434 by 300 ; by 5300. 10. Multiply 1234 by 600 ; by 1054. 11. 1417 x 34; 6417 x 27; 6946 x 123. 12. 340 x 20 x 16 ; 853 x 300 x 4 ; 803 x 101. NOTE. The teacher will readily supply additional examples for practice under each rule. They can be written on the blackboard, and copied by the pupils. DIVISION. 173 LESSON V. Division. 15. By DIVISION we find how many times one num- ber is contained in another larger number. The DIVIDEND is the number to be divided. The DIVISOR is the number by which we divide. The number of times the divisor is contained in the dividend is the QUOTIENT. The REMAINDER is what is sometimes left after dividing. 16. There are two methods of performing division. Ex. 1. How many times is 4 contained in 948 ? 1st Operation. 4)948(237 8 14 12 28 28 We begin at the left of the dividend to divide. 4 is contained in 9, 2 times. Place 2 at the right of the dividend, as the first figure of the quotient. 2 times 4 are 8, which we set under 9, and subtract. To the remainder, 1, we bring down 4, the next figure of the dividend, making 14. 4 in 14, 3 times. Place 3 in the quotient and multiply the divisor, and proceed as before, till all the figures are brought down and divided. The entire quotient is 237. 174 DIVISION. 2d Operation. 4)948 237 In this method, we do in the mind a part of what we wrote out in the 1st operation, and write the quo- tient under the dividend. 4 is contained in 9, 2 times and 1 over. We place 2 under 9 as the first figure of the quotient, and imagine the remainder 1 placed before 4, the next figure of the dividend, making 14. 4 in 14, 3 times and 2 over. We place 3 under 4, and imagine 2 set before 8, making 28. 4 in 28, 7 times. The entire quotient is 237, as before. 1 7. This second method is sometimes called SHORT DIVISION, and is used when the divisor is not more than 12. The first method is called LONG DIVISION, and is used when the divisor is more than 12. 2. 9)1251 9)1251(139 7)28345(4049 9 28 139 35 34 27 28 81 65 3. 7)28345 81 63 4049 2 Eem. 2 Eem. Work the following examples by Short Division : 4. 4)57432 6)31740 8)17344^ 9)5562 618 DIVISION. 175 5. 5)74035 4)67434 6)10746 8)84755 105943 Kern. Prove all the examples in Division, by multiplying the quotient and divisor together and adding the re- mainder, if there is any, to the product. The result must equal the dividend. "Work the following by both methods : 6. 6)74789 7)78743 8)97145 9)23474 EXAMPLE 7. Divide 9274 by 35. Here, of course, we use Long Division. Operation. Proof. 35)9274(264 264 70 35 227 1320 210 792 34 174 140 9274 34 Kem. How many times is 35 contained in 92? 3 in 9, 3 times; but, multiplying 35 by 3, we have 105, which is more than 92; we therefore take a quotient figure one less, 2, and find 2 times 35 = 70, which is less than 92. So, to find the second quotient figure : 3 in 22, 7 times. Finding 7 too large, we try 6. 8. Divide 3754 by 24. Quo. 156. Kem. 10. 9. Divide 17473 by 56. Quo. 312* Rem. 1. 176 DIVISION. 10. Divide 3746 by 36. How can you know whe- ther your quotient is correct ? 11. Divide 2756 by 48. Operation. The divisor, 48, is nearly 50. To 48)2756(57 find the quotient figures we say, 5 in 240 27, 5 times ; multiplying the divisor by 5, we have 240, less than 275 ; 356 subtracting, we find 35 for remain- 336 der, a number less than the divisor. So, 5 in 35, 7 times, &c. 20 Rem. 12. Divide 9437 by 27; by 31 ; by 35 ; by 14. 13. Divide 10743 by 45 ; by 450 ; by 412. 14. Divide 12345 by 103 ; by 301 ; by 345. 15. Since there are 365 days in one year, how many years are there in 2000 days ? 16. If I pay 9744 dollars for 112 acres of land, how much is it an acre ? 17. How many cows can I buy for 581 dollars, if each cow is worth 83 dollars ? 18. If the dividend is 7839, and the divisor is 214, what are the quotient and remainder \ 19. Add together 359, 895, and 1054; subtract 1343 from the sum ; multiply the remainder by 8, and divide the product by 4. What is the quotient ? NOTE. The same example expressed by means of signs is 359 -f 895 + 1054 1343 x 8 -j- 4 = ? 20. 874 + 917-1056 x 6 ~ 5 ? Quotient 882. 21. 3846 + 1904 + 3841 3489 x 100 ~ 75 = ? 22. 804 x 200 -f- 25 + 3568 - 10000 = 2 - t / YB I744P 7 8- 4 M30G004 THE UNIVERSITY OF CALIFORNIA LIBRARY 7 / V E X A. B L K s MATHEMATICAL 1. First Lessons in Numbers. An illustrat Mental Arithmetic, for the use of Farni; Adapt i .-d to the OBJECT METHOD. 30 cents. 2. Mental Arithmetic. After the inductive ms in Written Arithmetic. I Academies. 45 cents. 3. Elements of Written Arithmetic. In which the fun dan tioTis on Abstract and Denominate Numbers, and i cation*, are thoroughly explained and illustrated by*immer amples, adapted to the business of practical life. 1, 00. 4. High School Arithmetic. FOR THE USE OF SCHOOLS AND COLLEGES.- tg Ol lllU! on the fundamental principles strated by a greater variety and num- this v ork the reaso developed, an locations an -. In addition to the subjects usually rithnietic, it will contain several cinq ai bers, Progressions, .Logarith ; i 5. Elementary Algebra.- For Schools an 6. Higher Algebra hapters on the Theory of Determinants, and othf sons from the modern higher Algebra, for the use of Univ< Students. 7. Le^sndre's Geometry. To the complete translation of the i ot *he standard works of Legendre will be appended ma- in Geometrical Analysis, with hints for the soluti Also, notes on the application of the method of Limits to ! stnitiuu of theorems in Elementary Geometry. 8. Analytical Geometry. PART FIRST. Plane Co-ordin Point. Straight Line, Conic Sections, some of the liiidH-r PI:. 'raic and Transcendental, Also, the Meth .The Point and Straight Line in S ; Surfaces of the Second Order, Cones, Cyliin n, Conoids, Helicoid- Both parts will < RICHARDSON Sc COMPANY, Publishers New York. :