4. What may a broker demand, when he sells goods to the value of 5081. 17s. 10d. and I allow him 11 per cent. ? Ans. £7 12s. 8d. ENSURANCE, 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 e asurance of 7251. 8s. 10d. at 121 per cent.? Ans. £90 13s. 71d. 2. What is theesurance of an East-India ship and cargo, valued at 123425 dollars, at 15 per cent.? Ans. $19130, 87ets. 5m. 3. A man's house estimated at 3500 dollars, was sured against fire, for 13 per cent. a year: what ensurance did he annually pay? Ans. $61, 25cis. 4400. 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 consist 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 consist 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 547. for seven months and ten days, at 6 per cent. SHORT PRACTICAL RULES, c. S. 10 days=1)5,4 Interest for one month. 7 37,8 ditto for 7 months. Ans. 39,6 shillings£1 19s. 7,2d. 12 7,2 12. 2. What is the interest of 427. 10s. for 11 months, at 6 per cent. ? £. s. £. 42 10 = 42,5 decimal value. Therefore 4,25 shillings interest for 1 month. 11 £. 8. d. 69 Ans. 46,75 Interest for 11 mo. = 2 3. Required the interest of 941. 7s. 6d. for one year, five months and a half, at 6 per cent. per annum ? Ans. £8 5s. 1d. 3,5grs. 4. What is the interest of 12. 18s. for one third of a month, at 6 per cent. ? Ans. 5,16d. II. FOR FEDERAL MONEY. RULE. 1. Divide the principal by 2, placing the separatrix as usual, 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 num ber 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 7 months? 1280,70 Ans. 1280,7cts.=$12, 80cts. 7m. 2. Required the interest of 10 dols. 44 cts. for 3 years, 5 months and 10 days. 2)10,44 10 days) 5,22 Interest for 1 month. 41 months. 5,22 208,8 214,02 ditto for 41 months. 215,76cts. Ans. $2, 15cts. 7m.+ 3. What is the interest of 342 dollars for 11 months? Theis 171 Interest for one month. 11 Ans. 1881cts. $18, 81cts. 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 dollar; and $25, 40 cts. is 25 cts. 4 m. &c. which gives the following RULE II. Multiply the principal by half the number of months, and the product will show the interest for the given time, in cents and decimals of a cent, as above. EXAMPLES. 129 1. Required the interest of 316 dollars for 1 year and 10 months. 11= 'e number of mo. 6 Ans, 3476cts.= $34, 70cls 2. What is the interest o. 364 dols 25cts. for 4 months? $cts. 364, 25 2 half the months. 728, 50cts. Ans.=$7, 28cts. 5m. III. When the principal is given in federal money, at per cent to find how much the monthly interest will be in New-England, &c. currency. RULE. Multiply the given principal by ,03 and the product will be the interest for one month, in shillings and decimal parts of a shilling. EXAMPLES. 1. What is the interest of 325 dols. for 11 months ? ,03 9,75 shil. int. for 1 month Ans. 107,25s. =£5 78. 3d. 2. What is the interest in New-England currency, of 31 dols. 68 cts. for 5 months? Principal 21,68 dols. SHORT PRACTICAL RULES. IV. When the principal is given in pounds, shillings, &c. New-England currency, at 6 per cent. to find how much the monthly interest will be in federal money. RULE. Multiply, the pounds, &c. by 5, and divide that product by 3, the quotient will be the interest for one month, in cents, and decimals of a cent, &c EXAMPLES. 1. A note for £411 New-England currency has been on interest one month; how much is the interest thereof in federal money? £. 411 5 3)2055 Ans. 685cts.$6, 85cts. 2. Required the interest of 391. 18s. N. E. currency, for 7 months? £ 39,9 decimal value. 5 3)199,5 Interest for 1 mo. 66,5 cents. 7 Ditto for 7 months, 465,5cts.$4, 65cts. 5m. Ans. V. When the principal is given in New-England and Virginia currency, at 6 per cent. to find the interest for a year, in dollars, cents and mills, by inspection. RULE. Since the interest of a year will be just so many cents as the given principal contains shillings, therefore, write down the shillings and call them cents, and the pence in the principal made less by 1 if they exceed 3, or by 2 when they exceed 9, will be the mills, very nearly. |