COMPOUND INTEREST, Is calculated by adding the interest to the principal at the end of each year and making the amount the principal for the succeeding year; then the given principal subtracted from the last amount the remainder will be the compound interest. A concise and easy Method of casting Compound Interest, at 6 per Cent. on any sum in Federal Money. RULE. WI For 7 years, by 150,3630 8 years 159,3848 9 years OF -10 years 179,0847 6 years 1. Ho 141,8519 11 years 189,8298 Note. 1. Three of the first or highest decimals, in the above numbers, will be sufficiently accurate for most operations ; the product, remember-4.60 and it will shew the compound interest. this added to the amount will give the answer. 3. Any sum of money at Compound Interest, will double itself in 11 years, 10 months, and 22 days. EXAMPLES 1. What is the compound in- 2. What is the amount of $236 at terest of S 56 75 for 11 years ? compound interest, for 4 years, 7 months and 6 days ? OPERATION. OPERATION. 5 6, 7 5 1 2 6,2 4 7 6 I 8 9,8 2 ? 2 3 6 75 p 4 8 5 6 5 1 0 7 5 ! $ 29 7,9 4 4 3 3 6 Amount 3,6 [ for 4 years: S 10 7,727 9 5 7 5 Amount, 5 6,7 5. Principal subtracted. 1 8 7 6 6 4 -[mo, 6 days. $ 5 0,9 7 Cempound interest. $ 1 0,1 2 5 9 8 4 Interest for 2 9 7,9 4 4 Amount for 4 years [added S 30 8,5 69 Answer: SUPPLEMENT TO 5. Enterest. QUESTIONS. 1. WHAT is interest ? 2. What ie understood by 6 per cent ? 3 PER CENT? 8 PER CENT? &C. 3. WHAT per cent, per annum is allowed by Law to the Lender for the use of his Money? 4. WHAT is understood by the PRINCIPAL? the RATE ? the AMOUNT? 5. Of how many kinds is interest ? in what does the difference consist ? 6. How is simple interest calculated for one year, in Federal Money ? 7. For more years than one, how is the interest found ? 8. When there are months and days what is the method of procedure? 9, WHAT other METHOD is there of casting interest on stums in Federal Money? 10. When the days are a less number than 6, so that 6 cannot be contained in them, what is to be done ? ll. How is simple interest cast in pounds, shillings, pence, and farthings? 12. When partial payments are made, at different times, how is the interest cal. culated? EXERCISES. 1. What is the interest of 916 Dolls. 2. What is the interest of 93 dolls. 72 cts. for 1 year and 4 months ? 17 cts, 11 days? Ans. 17 cts. Ana. Dolls. 73,337. 3. What is the interest of Dolls. 5,19. 1 m. 4. What is the interest of Dolls. 1,07 for 3 years 6 months, and 15 days? Ans. 22 cts. 7 m UN be 7. SUPPOSING a note of Dolls. 317,92 dated July 5, 1797, on which were the following payments; Sept. 13, 1799, Dolls. 208,04. March 10, 1800 Dolls. 76; what was the sum due Jan, 1, 1801 ? Ans. Dolls. 83,991. COMPOUND MULTIPLICATION is when the Multiplicand consists of several denominations. It is particularly useful in finding the value of Goods. The different denominations in what was formerly called Lawful Money, render this rule with some others in Arithmetic, as Compound Division and Practice, rules of great usefulness, quite tedious, and the variety of cases necessarily introduced, extremely burthensome to the memory. This lumber of the mind might be almost wholly dispensed with, were the habit of reckoning in Federal Money generally adopted thro' the U, States. For important reasons, Pounds, Shillings, Pence, and farthings ought to fall wholly into disuse : Federal Money is our National Currency ; the Scholar might encompass the most useful rules of. Arithmetic in half the time ; the value of commodities, bought and sold, might be cast with half the trouble, and with much less liability to errors, were all the calculations in money universally made in Dollars, Cents, and Mills. But this, to be practised must be taught; it must be taught in our schools, and so long as the prices of goods, and almost every man's accounts are in Pounds, Shillings, Pence and Farthings, this mode of reckoning must not be left untaught. To comprise the greater usefulness, and also to shew the great advantage which is gained by reckoning in Federal Money, I have contrasted the two modes of account, and in separate columns, on the same page, have put the same questions in Old Lawful, and in Federal Money. IN ALL CASES OPERATION. CASE, 1. MULTIPLY the price and the quan- many places for cents and mills as EXAMPLES there are places of cents and mills in the price. EXAMPLES 1. What will 7 yards of cloth cost at 9 5 price of 1 yard. Dolls. 1,57 requal to 995) per yard ? OPERATION D. As there are 1, 57 Price. two decimal I SAY, 7 times 5 is 35 pence/11. I 7 quantity. places in the set down '11 and carry 2, saying, 7 price so I make imes 9 is 63, and 2 I carry is 658= 1nø.10,99price of 7uds. two in thic pro(.3 53. wbich I set down. duct. 8. 5 cts. Pounds, Shill. Pence, Farthings. Dollars, Cents, Mills, 2. What will 9 pounds of sugar cost 2. What will 9 pounds of sugar cost at 10d. per pound? Ans. 7/6. Ans. Dolls. 1,251 CASE 2. When the quantity exceeds 12 and is any number within the Multiplication Table, multiply by two such numbers, as when multiplied together, will produce the given quantity. If no two numbers will do this' exactly, multiply by two such numbers, as come the nearest to it, and by the deficiency or excess, multiply the multiplicand, and this product added to, or subtracted from the first product, as the case may require,gives the answer. EXAMPLES. 1. What will 42 yards of cloth cost 4. What will 42 yards of cloth cost at 15/9 per yard ? at Dolls. 2,625 per yard ? OPERATION. D. cts. m. 2, 6 2 5 Vultiplied by 6 4 2 gi th DI 4 14 6 price of byards. Multiplied by 7 Ans. 33 16 price of 42 yds. Because 6 times 7 is 42,-I multiply the price of 1 yard by 6 and this proPrict by 7, as the rule directs. |