Add 6.2 121.306 75 2.7 and .0007 ton gether. 121.306 .75 2.7 .0007 Sum= 130.9567 What is the sum of 6.57 1.026 .75 146,5 8.7 526. 3.97 and .0271 ? Answer 693.5431. What is the sum of 4.51 146.071 .507 .0006 132. 62.71 .507 7.9 and .10712 ? Answer 354.31272. SUBTRACTION OF DECIMALS. Write the figures of the subtrahend beneath those of the minuend according to the denomination of their places, as directed in the rule of addition ; then, beginning at the right hand, subtract as in whole numbers, and place the decimal point in the difference exactly under the other two points. EXAMPLES. From 38.765 take 25.3741 25.3741 Difference =13.3909 From 2.4 take .8472 Diff.=1.5528 From 71.45 take 8.4837248. Difference = 62.9662752. Diff. = 1.6588. MULTIPLICATION OF DECIMALS. Set the multiplier under the multiplicand without any regard to the situation of the decimal point ; and having multiplied as in whole numbers, cut off as many places for decimals in the product, counting from the right hand towards the left, as there are in both the multiplicand and multiplier : but if there be not a sufficient number of places in the product, the defect may be supplied by prefixing ciphers thereto. For the denominator of the product being an unit, prefixed to as many ciphers, as the denominators of the multiplier and multiplicand contain of ciphers, it follows, that the places of decimals in the product, will be as many as in the numbers from whence it arose. EXAMPLES. Multiply 48.765 by .003609 .003609 438885 292590 146295 Product=.175992885 Multiply .121 by .14 484 121 Product=.01694 Multiply 121.6 by 2.76 2.76 7296 8512 2432 Product =335.616 Multiply .0089789 by 1085 Product = 9.7421065 Product = .03379399401. DIVISION OF DECIMALS. Divide as in whole numbers ; observing that the divisor and quotient together must contain as many decimal places as there are in the dividend. If, therefore, the dividend have just as many places of decimals as the divisor has, the quotient will be a whole number without any decimal figures. If there be more places of decimals in the dividend, than there are in the divisor, point off as . many figures in the quotient for decimals, as the decimal places in the dividend exceed those in the divisor; the want of places in the quotient being supplied by prefixing ciphers. But if there be more decimal places in the divisor, than in the dividend, annex ciphers to the dividend, so that the decimal places here may be equal, in number, to those in the divisor; and then the quotient will be a whole number, without fractions. When there is a remainder, after the division has been thus performed, annex ciphers to this remainder, and continue the operation till nothing remains, or till a sufficient number of decimals shall be found in the quotient. 0 Divide 63.72413456922 by 2718 2718)63.724134569220.02344522979 =quotient. 5436 9364 12101 12293 14214 6245 8096 26609 21472 24462 There being 11 decimal figures in the dividend, and none in the divisor, 11 figures are to be cut off in the quotient; but as the quotient itself consists of but 10 figures, prefix to them a cipher to complete that number. Divide 1.728 by .012 .012)1.728(144=quotient. 12 52 48 48 0 Because the number of decimal figures in the divisor and dividend, are alike, the quotient will be integers. Divide 2 by 3.1416 1 8849 6 115040 207920 194240 57440 260240 o С |