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ANOTHER METHOD. Write down the given principal in cents, which multiply by tie rate, and divide by 100 as before, and you will have the interest for a year, in cents, and decimals of a cent, as follows:
9. What is the interest of $73, 65 cents for a year, at 6 per cent. : Principal 7365 cents.
7 per cent:?
Ins. 441,90cts.-=441%cts. Or 94, 41cts. 9u. 10. Required the interest of $85, 45cts. for a year, at
Fins. 398, 15 cente,$5,98cts. i jin.
CASE II. To find the simple interest of any sum of money, for any number of
1st: Find the interest of the given sum for one year.
2d. Multiply the interest of one vear by the given number of years, and the product will be the answer for that time.
3d. If there be parts of a year, as months and days, work for the months by the aliquot parts of a year, and for the days by tie Rule of Three Direct, or by allowing 30 days to the month, and taking aliquot parts of the
* By allowing the month to be so days, and taking aliquot parts thereof, you will have the intcrest of any ordina:'y sum sulhciently exact for common use; but if the sum be very Bre, primar sar,
As 283 days : is to the interest of one year : : so is the irenlumber of VS · to the interest inoire.
EXAMPLES. 1. What is the interest of 751. 8s. 4.1. for 5 years and 2 inonths, at 6l. per cent. per a!?nun?
d. 1 8 4
6 No. 3)4 10 6 Interest for 1 year. 452 10 20
29 12 do. for 5 years.
0 15 1 do. for 2 inonths. 10150
... What is the interest of 6-1 dollars, 58 cents, for 3 years, 5 months, and 10 days, it 5 per cent. ?
322,90 Interest for 1 year in cents, per 3
969, o do. for a years. 4 mo. } | 107,65 din. for - inouths. 1 mo.
至 26,90 do for 1 month. 10 days, 8,96 do. for 10 days.
Ans. 1119,19=1119cts. Or S:1, 12, 1, $18. 3. What is tlie interest of 789 lollars for years, at 6
jins. S94, 68cts. 4. Of 37 dollars 50 cents for 4 years at 6 per cent. per annam?
Ans. 900cts. Or 89 5. Of 325 dollars 41 cents, for 5 years and 4 months, at 5 per cent. ?
Ans. (954, Oscts. 5m. 6. Of 325l. 123. 3d. for 5 years, at 6 per cent. ?
Firs. 4,97 13s. 8d. 7. Of 1741. 10s. 64. for S ani a half years at 6
per cent. ?
Fris. 656 138. 8. Of 150 16s. Sc. for 4 years and months, at 6 per ant. ?
ins. 641 9s. 78
9. Of 1 dollar for 12 years at 5 per cent. ?
Ans. 60cts. LO. Of 215 dollars 34 cts. for 4 and a half years, at 3 and a half per cent. ?
Ans. $33, 9icts. 6m. 11. What is the amount of 324 dollars, 61 cents, for 5 years and 5 months, at 6 per cent. ?
Ins. $430, 10cts. 3160? 12. What will scool. amount to in 12 years and 10 months, at 6 per cent. ?
ins. £5310. 13. What is the interest of 2571. 5s. 1d. for 1
and 3 quarters, at 4 per cent. ? Ans. £18 Os. 1d. 3qrs.
14. What is die interest of 279 dollars, 87 cents for 2 years and a half, at 7 per cent. per annum:
is. $48, Sēcis. im 15. What will 2791. 153. 6e. amount tovin s
and a half at 54 per cent. per annum?
Ans. £331 Is. 62. -- 16. What is the amount of 541 dols. 60 cts. for 5 years and 5 quarters, at 7 and a half per cent per annum?
Sinis. $488, 9incés. 17. What will 730 dols. amount to at 6 per cent. in 5 ycars, 7 months and 12 days, or of a year
Ans. $975, 99cts. 18. What is the interest of 1925l. at 5 per cent. per annum, from March 4th, 1796, to March 29th, 1799, (allowing the year to contain 565 days?) Ans. $280.
Nore.The Rules for Simple Interest serve also to calculate Commission, Brokerage, Insurance, or any thing elsc estimated at a rate per cent.
COMMISSION, IS an allowance of so much per cent to a factor or correspondent abroadl, for buying and sclNng goods for his employer
1. What will the commission of 8431. 10s. come to at 5 per cent. ?
£49 Ss. 61. 2. Required the commission on 964 dols. 90 cts. at 21
Ans. $21, 71cts. 3. What may a factor demand on 14 per cent. cominis. sion, for laying out 3568 dollars ? ins. $62, 44cts.
BROKERAGE, IS an allowance of so much per cent. to persons assisting merchants, or factors, in purchasing or selling goods.
1. What is the brokerage of 750!. Es. 4.1. at 6s. Sd. per cent. ? £. S.
d. 750 8 4 Here I first find the brokerage at 1
1 pound per cent, and then for the
given rate, which is of a pounil. 7,50 8 4 20
f. s. d. arg.
6 8 = })7 10 1
Ans. £2 10 0 11
1,00 2. What is the brokerage upon 4125 dols, at or 75 sents per cent. ?
ins. $30, 93cís. 73111. 3. If a broker sells goods to the amount of 5000 (lots. what is his demand at 65 cts. per cent.?
Ans. $90, 50:** $
4. What may a broker demand, when he sells goods ir the value of 508l, 17 à 10d. and I allow him 14 per cent.!
Ans. £7 12s. 8d.
INSURANCE, IS a premiuin ar so much per cent. allowed to persons and oilices, for making good the loss of ships, houses, mer. chandize, &c. which may happen from storms, fire, &c
1. What is the insurance of 725l. Es. 101. at 124 per cent,
Ans. 290 13s. 71d. 2. What is the insurance of an East-India ship and cargo, valued at 123-125 dollars, at 15) per cent. ?
Ans. $191,0, 87cts. 5m. 5. A man's house estimated at 3500 dollars, was insu. red arainst fire, for li per cent. a year : what insurance did he annually pay?
Ans. $61, 25cts.
SHORT PRACTICAL RULES,
or months and days.
RULE, 1. If the principal consists of pounds only, cut off the unit figure, and as it then stands it will be the interest for one month, in shillings and decimal parts.
2. If the principal consists of pounds, shillings, &c. re duce it to its decimal value; then remove the decimal point one place, or figure, further towards the left hand, and as the decimal then stands, it will shew the interest for one month, in shillings, and decimals of a shilling.
1. Required the interest of 541. for seven months ans) Lco days, ni o per cent