I is 327 of 324, It is contained 56 times and 220 over. and 220 is žż 9 of 324. Ans. 56 times and of another time. From the above examples, we deduce the following general rule for the remainder : When the division is performed, as far as it can be, if there is a remainder, in order to have the true quotient, write the remainder over the divisor in the form of a fraction, and annex it to the quotient. XI. We observed in Art. V. that when the multiplier is 10, 100, 1000, &c. the multiplication is performed by annexing the zeros at the right of the multiplicand. In like manner when the divisor is 10, 100, 1000, &c. division may be performed by cutting off as many places from the right of the dividend as there are zeros in the divisor. At 10 cents a pound, how many pounds of meat may be bought for 64 cents ? The 6 which stands in tens' place shows how many times ten is contained in 60, for 60 signifies 6 tens, and the 4 shows how many the number is more than 6 tens, therefore 4 is the remainder. The operation then may be performed thus, 6.4. The answer is 6,4 pounds. A man has 2347 lb. of tobacco, which he wishes to put into boxes containing 100 lb. each ; how many boxes will it take? It is evident that 100 is contained in 2300, 23 times, consequently it will take 23 boxes, and there will be 47 lbs. left, which will fill 47 of another box. The operation may be performed thus, 23.47. Answer 2347 In general if one figure be cut off from the right, the tens will be brought into the units' place, and hundreds into the tens' place, &c. If two figures be cut off, hundreds are brought into the units' place, and thousands into the tens' place, &c. And if three figures be cut off, thousands are brought into the units' place, &c. that is, the numbers will be made 10, 100, or 1000 times less than before. Hence to divide by 10, 100, 1000, fc. cut off from the right of the dividend as many figures as there are zeros in the divisor. The remaining figures will be the quotient, and the figures cut off will be the remainder, which must be written over the divisor, and annexed to the quotient. XII. We observed in Art. X, that any two numbers being given, it is easy to tell what part of the one the other is. Thus : What part of 10 yards are 3 yards ? Ans. 1 is ito of 10, and 3 is so of ten. What part of 237 barrels is 82 barrels ? Ans. 1 is zit of 237, and 82 is of 237. Fractions are properly parts of a unit, but by extension the term fraction is often applied to numbers larger than unity. This happens when the numerator is larger than the denominator, in which case there are more parts taken than are sufficient to make a unit. All fractions in which the numerator is equal to the denominator, as i, j, k, 1, &c. are equal to unity; all in which the numerator is less than the denominator are less than unity, and are called proper fractions; all in which the numerator is greater than the denominator, are more than unity, and are called improper fractions. Thus 3, 4, 5, are improper fractions. The process of finding what part of one number another number is, is called finding their ratio. What is the ratio of 5 bushels to 3 bushels, or of 5 to 3! This is the same as to say, what part of 5 is 3 ? The answer is The ratio of 5 to 3 is g. What part of 3 is 5? Answers. The ratio of 3 to 5 is What is the ratio of 35 yards to 17 yards. Answer 11 What is the ratio of 17 to 35 ? Answer i . To find what part of one number another is, make the number which is called the part (whether it be the larger or smaller) the numerator of a fraction, and the other number the denominator. Also to find the ratio of one number to another, make the number which is expressed first the denominator, and the other the numerator. XIII. A gentleman gave } of a dollar each to 17 poor persons ; how many dollars did it take? It took 4 of a dollar. But of a dollar make a dollar, consequently as many times as 5 is contained in 17, so many dollars it is. 5 is contained 3 times in 17, and 2 over That is, make 3 dollars, and there are of another dollar. Ans. 3 dollars. If 1 man consume zis of a barrel of flour in a week, how many barrels will an army of 537 men consume in the same time? They will consume 53. of a barrel make a barrel, therefore as many times as 35 is contained in 537, so many barrels it is. 537 (35 15}} barrels. Ans. parts make a "and 12 35 is contained 15 times in 537 and 12 over, which is } } of another barrel. Numbers like 3, 151, which contain a whole number and a fraction, are called mixed numbers. The above process by which y was changed to 35, and 53 to 15}}, is called reducing improper fractions to whole or mixed numbers. Since the denominator always shows how many of the whole one, it is evident that any improper fraction may be reduced to a whole or mixed number, by the following rule : Divide the numerator by the denominator, the quotient will be the whole number. If there be a remainder, write it over the denominator, and annex it to the quotient, and it will form the mixed number required. XIV. It is sometimes necessary to change a whole or a mixed number to an improper fraction. A man distributed 3 dollars among some beggars, giving them of a dollar apiece; how many received the money ? That is, in 3 dollars, how many fifths of a dollar ? Each dollar was divided equally among 5 persons, consequently 3 dollars were given to 15 persons. That is, 3 dollars are equal to * of a dollar. A man distributed 184 bushels of wheat among some poor persons, giving them of a bushel each ; how many persons were there? This question is the same as the following: In 187 bushels, how many of a bushel ? That is, how many 7ths of a bushel ? In 1 bushel there are 7, consequently in 18 bushels there are 18 times 7 sevenths ; that is, 146, and more make i.. Answer 129 persons. Reduce 2847 to an improper fraction. That is, in 2817 how many 25 Since there are se in 1, in 28 there must be 28 times as many. 28 times 25 are 700, and 17 more are 717. Ans. 717 25. Hence to reduce a whole number to an improper fraction with a given denominator, or a mixed number to an improper fraction : multiply the whole number by the denominator, and if it is a mixed number add the numerator of the fraction, and write the result over the denominator. XV. A man hired 7 labourers for 1 day, and gave them of a dollar åpiece; how many dollars did he pay the rohole ? If we suppose each dollar to be divided into 5 equal parts, it would take 3 parts to pay l man, 6 parts to pay 2 men, &c. and 7 times 3 or 21 parts, that is, az of a dollar to pay the whole. ? of a dollar are 41 dollars. Ans. 4} dollars. A man bought 13 bushels of grain, at of a dollar a bushel ; how many dollars did it come to ? of a dollar are 5 shillings. 13 bushels at 5 shillings a bushel, would come to 65 shillings, which is 10 dollars and 5 shillings. In the first form, 13 times of a dollar are one of a dollar ; that is 104 dollars, as before. A man found by experience, that one day with another, his horse would consume 14 of a bushel of oats in a day; how many bushels would he consume in 5 weeks or 35 days? If we suppose each bushel to be divided into 37 equal parts, he would consume 13 parts each day. In 35 days he would consume 35 times 13 parts, which is 455 parts. But the parts are 37ths, therefore it is * = 12 14 bushels. 35 13 105 35 = 1234 455 This process is called multiplying a fraction by a whole number. Multiply 403 by 48. The fraction signifies that 1 is divided into 1372 equal parts, and that 253 of those parts are used. To multiply it by 48, is to take 48 times as many parts, that is, to multiply the numerator 253 by 48. 253 14 = 81144 12144 The product of 253 by 48 is 12144 ; this written over the denominator is 133140 which being reduced is 849. Ans. To multiply a fraction then, is to multiply the number of parts used; hence the rule : multiply the numerator and write the product over the denominator. Note. It is generally most convenient, when the numerator becomes larger than the denominator, to reduce the fraction to a whole or mixed number. It is sometimes necessary to multiply a mixed number. Bought 13 tons of iron, at 9744 dollars a ton ; what did it come to ? In this example the whole number and the fraction must be multiplied separately. 13 times 97 are 1261. 13 times 14 are 4 equal to 437; this added to 1261 makes 126514 dollars. Ans. |