9. Or 1 dollar for 12 years, at 5 per cent.! Ans. 60cts. 10. Or 215 dollars 34 cts. for 4 and a half years, at 3 and a half per cent.! Ans. $33,91cls. 6m. 11. What is the amount of 324 dollars, 61 cents, for 5 years and 5 months, at 6 per cent.? . Ans. $430,10cts. 8 om 12. What will 30001. amount to in 12 years and 10 months, at 6 per cent.? Ans. £5310. 13. What is the interest of 2571. 5.s ld. for 1 year and 3 quarters, at 4 per cent 3 £18 Os.) d. 3qrs. 14. What is the interest of 279 dollars, 87 cents, for 2 years and a hall, at 7 per cent. per annum ? Ans. 48,97cts. 7m. 15. What will 2791. 135. 8d. amount to in 3 years and a half, at 54 per cent. per annum ? Ans. £331 18. 6d 16. What is the amount of 341 doHs. 60 cts. for 5 years and 3 quarters, at 7 and a half per cent. per annum ? Ans. 8488,91 cts. 17. What will 730 dollars amonnt to at 6 per cent. in 5 years, 7 months and twelve days, or is of a year ? Ans. $975,99cls. 18. What is the interest of 18251. at 5 per cent. per annum, from March 4th, 1796, to March 29th, 1799, (allowing the year to contain 365 days ?) Ans. £280. Note.The Rules for Simple Interest serve also to calculate Commission, Brokerage, Insurance, or any thing else estimated at a rate per cent. COMMISSION, IS an allowance of so much per cent., to a factor or correspondent abroad, for buying and selling goods for his employer. EXAMPLES. 1. What will the commission of 8431. 108, come to at 5 per cent. per cert. ? 6100 £42 3s. Ed. 2. Required the commission on 961 dols. 9Octs, at 210 Ars. $ 21, 71 cls 3. What may a factor demand on 14 per cent. commission for laying out 3568 dollars ? Ans. $62. 44cls. BROKERAGE, Isan allowance of so much per cent. to persons assisting merchants, or factors, in purchasing or selling goods. EXAMPLES. 1. What is the brokerage of 7551 83. 4d. a: 6s. 8d. per cént ? £. 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 pound, 7,50 8 20 £. s. d. qrs 6 8=})7 10 1 sins. £2 10 03 4 S. d. 1.00 2. What is the brokerage upon 4125 dols. at or 75 cents per cent.? Ans. $30, 93cts. 7m. 3. If a broker sells goods to the amount of 5000 dols. what is bis demand at 65 cts. per cent.? Ans. $32, 50cts. 4. What may a broker demand, when he sells goods to the value of 5081. 175. 10d. and I allow him 11 per cent? Ans. £7 12s. 8d. INSURANCE, IS a premium at so much per cent, allowed to persons and offices, for making good the loss of ships, houses, merchandise, &c. which may happen from storms, fire, &c. EXAMPLES 1. What is the insurance of 725l. 8s. 10d. at 124 per cent. ? Ans. £90 135.74d. 2. What is the insurance of an East-India ship and cargo, valued at 123425 dollars, at 154 per cent. ? Ans. $19130, 87 cts. 5m. 3. A man's house estimated at 3500 dollars, was in gured against fire, for 14 per cent a year : what insurance did he annually pay? Ans. $61, 25cts. SHORT PRACTICAL RULES, For calculating Interest at 6 per cent. either for months, or months and days. I. FOR STERLING MONEY. RULE. 1. If the principal consists of pounds only, cut off de 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. reduce 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 show the interest for one month in shillings and decimals of a shilling. EXAMPLES. 1. Required the interest of 541. for seven months and sen days, at 6 per cent. 10 days})5,4 Interest for one month. 7 115,4 37,8 ditto for 7 months. 1,8 ditto for 10 days. Ans. 39,6 shillings=£1 198. 7,2d. 12 7,2 2. What is the interest of 421. 10s. for 11 months, at 6 per cent ? £. 42 10 - -42,5 decimal value. Therefore 4,25 shillings interest for 1 month. 11 d. Ans. 46,75 Interest for 11 mo. = 2 69 3. Required the interest of 94% 7s, 6d. for one year, five months and a half, at 6 per cent. per annum ? Ans. £8 58. Id. 3,5qrs. 4. What is the interest of 121. 18s. for one third of a month, at 6 per cent. ? Ans. 5,160 II. FOR FEDERAL MONEY. RULE 1. Divide the pricipal by 2, placing the separatsix as agual, and the quotient will be the interest for one month in cents, and decimals of a cent; that is, the figures at the left of the separatrix will be cents and those on the right decimals of a cent. 2. Multiply the interest of one month by the given number of months, or months, and decimal parts thereof, or for the days, take the even parts of a month, &c EXAMPLES 1. What is the interest of 341 dols. 52 cts. for 74 months ? 2)341,52 Or thus, 170,76 Int. for 1 month. 170,76 Int. for I'month. X7,5 months, 71 85380 1195,32 do. for 7 mo.: 119332 85,38 do. for $ mo. $ cts. m. 1280,700cls,=12,807 0,70 Ans. 1280,7cts.812, 80cts. 7m. 2. Required the interest of 10 dols. 44 cts. for 3 years, 5 months and 10 daye. 2)10,44 10 days=}) 5,22 Interest for 1 month. 41 months. 215,76cts. Ans. =$2, 15cte. 7m. + 3. What is the interest of 342 dollars for 11 months The } is 171 Interest for one month. 11 Ans. 1881 cts.=$18, 81 cts. Note.To find the interest of any sum for 2 months, at 6 per cent. you need only call the dollars so many cents, and the inferior denominations decimals of a cent, and it is done : Thus, the interest of 100 dollars for two months, is 100 cents, or 1 dollár ; and $25, 40 cts. is 25 cts. 4m. &c. which gives thie following RULE II. Multiply the principal by half the number of months, and the product will show the interest for the given time, iz cents and decimals of a cent, as above. . |