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OPERATION.

18.£. 15s. 6d. 18.775£.; 18.775 x = $62.58 Ans.

=

14. Change 15£. 15s. 9d. of the old currency of New York, to dollars and cents.

OPERATION.

15£. 158. 9d.=15.7875£.; 15.7875×¥=$39.46.83 Ans. 15. Change 176£. 19s. 9d. sterling to United States Ans. $786.61+.

currency.

OPERATION.

176£. 19s. 9d. =176.9875£.; 176.9876×=$786.61+.

III. To find the value of any given decimal in the terms of the integer.

16. What is the value of .9875£. ?

OPERATION.

.9875
20

19.7500

12

9.0 0 0 0

Hence the following

Ans. 19s. 9d.

This question is performed by the same principle we adopted in finding the value of a vulgar fraction in the known parts of the integer.

RULE.

Multiply the given decimal by that number which it takes of the next denomination to make one of that greater, and cut off as many places for a REMAINDER, on the RIGHT hand, as there are places in the given decimal. Multiply the REMAINDER by the next lower denomination, and cut off for a remainder as before, and so proceed, until the decimal is reduced to the denomination required; the several denominations standing at the LEFT hand are the answers required. 1. What is the value of .628125 of a £?

Ans. 12s. 6d.

2. What is the value of .778125 of a ton ?

Ans. 15cwt. 2qr. 7lb.

3. What is the value of 75 of an ell English?

Ans. 3qr. 3na.

4. What is the value of .965625 of a mile ?

Ans. 7fur. 29rd.

5. What is the value of .94375 of an acre ?

Ans. 3R. 31p.

6. What is the value of .815625 of a pound Troy?

Ans. 9oz. 15dwt. 18gr.

7. What is the value of .5555 of a pound apothecary's weight? Ans. 63. 53. 09. 191gr.

Section 32.

EXERCISES IN DECIMALS.

1. What is the value of 15cwt. 3qr. 14lb. of coffee at. $9.50 per cwt. ?

Ans. 150.81+.

2. What cost 17T. 18cwt. 1qr. 7lb. of potash at $53.80 per ton?

Ans. $963.86+.

3. What cost 37A. 3R. 16p. of land at $75.16 per acre?

Ans. $2844.80+.

4. What cost 15yd. 3qr. 2na. of cloth at $3.75 per yard? Ans. $59.53+: 5. What cost 15% cords of wood at $4.62 per cord? Ans. $71.10+.

6. What cost the construction of 17m. 6fur. 36rd. of railroad at $3765.60 per mile ?

7. What cost 27hhd. 21gal. of $15.37 per hogshead?

Ans. $67263.03+. temperance wine at Ans. $420.24+.

8. What are the contents of a pile of wood, 18ft. 9in. long, 4ft. 6in. wide, and 7ft. 3in. high?

Ans. 611ft. 1242in.

9. What are the contents of a board 12ft. 6in. long, and 2ft. 9in wide ? Ans. 34ft. 54in. 10. Bought a cask of vinegar containing 25gal. 3qt. 1pt. at $0.37 per gallon; what was the amount? Ans. $9.70+. 11. Bought a farm containing 144A. 3R. 30p. at $97.621 per acre; what was the cost of the farm? Ans. $14149.52+.

12. Sold Joseph Punson 3T. 18cwt. 21lb. of salt hay, at $9.37 per ton. He having paid me $20.25, what Ans. $16.40+. 13. If of a cord of wood cost $5.50, what cost one cord? What cost 7 cords? Ans. $48.71+.

remains due ?

/ Section 33.

SIMPLE INTEREST.

INTEREST is the compensation, which the borrower of money makes to the lender.

PRINCIPAL is the sum lent.

AMOUNT is the interest added to the principal.

PER CENT., a contraction of per centum, is the rate established by law, or that which is agreed on by the parties, and is so much for a hundred dollars for one year.

GENERAL RULE.

Let the per cent. be considered as a decimal of a hundred dollars, and multiply the principal by it, and the product is the interest for one year; but, if it be required to find the interest for more than one year, multiply the product by the number of years.

NOTE. The decimal for 6 per cent. is .06; for 7 per cent. .07; for 8 per cent. .08; for 94 per cent. .0925; for 2 per cent. 025, &c. The decimals must be pointed off as in Multiplication of Decimal Fractions.

This rule is obvious from the fact, that the rate per cent. is such a part of every hundred dollars. Thus, 6 per cent. is of the principal.

NOTE. When no particular per cent. is named, 6 per cent. is to be understood, as it is the legal interest in the New England States generally. In New York the legal interest is 7 per cent.

1. What is the interest of $346 for one year?

OPERATION.

346

.06

$20.76

Ans. $20.76.

There being two places of decimals in the multiplier, we point off two in the product.

2. What is the interest of $67.87 for 5 years?

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3. What is the interest of $197 for 1 year?

Ans. $11.82.

4. What is the interest of $ 1728 for 3 years?

5. What is the interest of $69 for 2

Ans. $311.04.

years ?

6. What is the interest of $1775 for 7

7. What is the interest of $987 for 10

8. Required the interest of $69.17 for

9. Required the interest of $96.87 for

10. Required the interest of $1.95 for

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11. Required the interest of $ 1789 for 20 years.

Ans. $2146.80.

12. Required the interest of $666.66 for 30

years. Ans. $1199.98.

13. What is the amount of $98.50 for 5 years?

14. What is the amount of $168.13 for

Ans. $128.05.
11 years?
Ans. $279.09.

15. What is the amount of $75.75 for 17 years?

Ans. $153.01.

16. Required the amount of $675.50 for 100 years.

Ans. $4728.50.

II. To find the interest for months, at six per cent.

RULE.

Multiply the principal by half the number of months, expressed decimally as a per cent.; that is, for 12 months multiply by .06; for 8 months multiply by .04; for 7 months .035; for 1 month .005, and point for decimals as in the last rule.

NOTE. It is obvious, that if half the number of months were 12, it would be 1 per cent. a month, that is, half the months will be the per cent. Q. e. d.

1. What is the interest of $ 486 for 10 months ?

OPERATION.

486 principal.

.05 months decimal of the per cent.

$24.30 Ans.

2. What is the interest of $1728 for 18 months?

Ans. $155.52.

3. What is the interest of $16.87 for 20 months?

Ans. $1.68.

4. Required the interest of $118.15 for 30 months.

Ans. $17.72.

5. Required the interest of $97.16 for 17 months.

Ans. $8.25.

6. Required the interest of $789.87 for 23 months.

Ans. $90.83.

7. Required the amount of $978.18 for 27 months.

Ans. $1110.23.

8. Required the amount of $87.96 for 1 month.

Ans. $88.39.

9. Required the amount of $81.81 for 100 months.

Ans. $122.71.

10. Required the amount of $0.87 for 87 months.

Ans. $1.24.

III. To find the interest for any sum for months and days, at 6 per cent.

RULE.

To one half of the months expressed decimally as in the last rule, annex one sixth of the days. With this multiply

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