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Ans. 81.4211.

Ans. 99.999.

8. From 87.1 take 5.6789. 9. From 100. take .001. 10. From seventy-three take seventy-three thousandths.

Ans. 72.927.

11. From three hundred sixty-five take forty-seven ten

Ans. 364.9953.

thousandths. 12. From three hundred fifty-seven thousand take twentyeight and four thousand nine ten millionths. Ans. 356971.9995991.

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Hence, we deduce the following

RULE.

Multiply as in whole numbers, and point off as many figures for decimals in the product, as there are decimals in the multiplicand and multiplier; but, if there be not so many figures in the product, as in the multiplicand and multiplier, supply the defect by prefixing ciphers.

Ans..12649. Ans. 18.58922. Ans. .00000114.

Ans. 1137. Ans. 2.20947. Ans. .00046967. Ans. 22.09.

3. Multiply 18.07 by .007. 4. Multiply 18.46 by 1.007. 5. Multiply .00076 by .0015. 6. Multiply 11.37 by 100. 7. Multiply 47.01 by .047. 8. Multiply .0701 by. 0067. 9. Multiply 47. by .47. 10. Multiply eighty-seven thousandths by fifteen millionths. Ans. .000001305. 11. Multiply one hundred seven thousand and fifteen ten thousandths by one hundred seven ten thousandths. Ans. 1144.90001605. 12. Multiply ninety-seven ten thousandths by four hundred and sixty-seven hundredths. Ans. 3.886499. 13. Multiply ninety-six thousandths by ninety-six hundred thousandths. Ans. .00009216. 14. Multiply one million by one millionth. Ans. 1. 15. Multiply one hundred by fourteen ten thousandths. Ans. .14. 16. Multiply one hundred and one thousandth by ten thousand one hundred one hundred thousandths.

Ans. .01020201. 17. Multiply one thousand fifty and seven ten thousandths, by three hundred five hundred thousandths.

Ans. 3.202502135.

18. Multiply two million by seven tenths.

Ans. 1400000. thousandths by thirty Ans. 12012.12012. $51.75.

19. Multiply four hundred and four and three hundredths. 20. What cost 46lbs tea at $1.125 21. What cost 17.125 tons of hay at $18.875 per ton?

per

lb. ?

Ans. $323.234375.

22. What cost 18lbs. sugar at $.125 per lb. ?

Ans. $2.25.

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Divide as in whole numbers, and point off as many decimals in the quotient, as the number of decimals in the dividend exceed those of the divisor; but, if the number of those in the divisor exceed that of the dividend, reduce the dividend to the same denomination as the divisor by annexing ciphers. And, if the number of decimals in the quotient and divisor together are not equal to the number in the dividend, supply the defect by prefixing ciphers to the quotient.

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15. Divide one hundred forty-seven and eight hundred

twenty-eight thousandths by nine and seven tenths.

J*

Ans. 15.24.

16. Divide six hundred seventy-eight thousand seven hundred sixty-seven millionths by three hundred twentyeight thousandths. Ans. 2.069.

Section 31.

REDUCTION OF DECIMALS.

I. To reduce a vulgar fraction to a decimal.

1. Reduce § to a decimal.

OPERATION.

8) 5.000
.625

That the decimal .625 is equal to §, may be shown by writing it in a vulgar fraction and reducing it thus,

Ans.

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NOTE. It is also evident, that .625 is equal to §, because the numerators have equal ratios to their denominators.

Hence the following

RULE.

Divide the numerator by the denominator, annexing one or more ciphers to the numerator, and the quotient will be the decimal required.

NOTE. It is not usually necessary, that decimals should be carried to more than six places.

2. Reduce to a decimal.

3. Reduce to a decimal.

Ans. .75.

Ans. .875.

4. What decimal fraction is equal to ? Ans. .4375.

to a decimal.

5. Reduce
6. Reduce to a decimal.

Ans. .363636+:
Ans. .416666+.

II. Reduce compound numbers to decimals.

7. Reduce 8s. 6d. 3qr. to the decimal of a £.

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Write the given numbers perpendicularly under each other for dividends, proceeding orderly from the least to the greatest; opposite to each dividend on the LEFT hand, place such a number for a divisor, as will bring it to the next superior name, and draw a line between them. Begin at the highest, and write the quotient of each division, as decimal parts, on the RIGHT of the dividend next below it, and so on, until they are all divided; and the last quotient will be the decimal required.

Ans. .775.

8. Reduce 15s. 6d. to the fraction of a £.
9. Reduce 5cwt. 2qr. 14lb. to the decimal of a ton.

Ans. .28125.

10. Reduce 3qr. 21lb. to the decimal of a cwt.

Ans. .9375.

11. Reduce 6fur. 8rd. to the decimal of a mile.

Ans. .775.

12. Reduce 3R. 19p. 167ft. 72in. to the decimal of an Ans. .872595+.

acre.

NOTE 1. If it be required to reduce pounds, shillings, pence, and farthings, of the old New England currency, to dollars, cents, and mills; the pounds, shillings, &c. may be reduced to the decimal of a £; and if this decimal be multiplied by 10 and the product divided by 3, the quotient will be dollars and cents. But if the above decimal be multiplied by 10, and the product be divided by 4, the quotient will be the reduction of the old currency of New York to dollars and

cents.

NOTE 2. If it be required to bring English sterling money to dollars and cents, let the pounds, &c. be reduced to the decimal of a penny; then divide this decimal by, and the quotient is dollars

and cents.

13. Change 18£. 15s. 6d. of the old New England currency, to dollars and cents.

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