. Endorsements. $ 90 $ 12 December 19, 1825, $ 16 March 1, 1826, $108 October 16, 1827, $350 What was there due, August 31, 1828, interest at 6 per cent? Ans. $115,77+ $800,00 56,00 Operation, $856,00 300,00 $556,00 37,53 $593,53 90,00 Amount, $503,53 51,61 Pay't Sept. 17, 1825, less than the interest then due $555,14 $ 12 16 108 -$136,00 Due March 1, 1826, forming a new principal, Pay't Oct. 16, 1827, a sum greater than the interest then due, time of settlement, (10% months.) Balance due, August 31, 1828. $110,00 5,77 $115,77+ $500. January 1, 1830. 2. For value received, I promise to pay Peter Trusty, or order, five hundred dollars, with interest. WILLIAM Payson. On this note were the following Endorsements. April 1, 1830, received $40 $ 8 $12 April 1, 1831. $30 How much remains due August 16, 1831, interest at 6 Ans. $455,57, . per cent ? COMPOUND INTEREST Is that which arises both from the principal and interest ; that is, when the interest is added to the principal at the end of the year, and on that amount the interest cast for another year and added as before ; and so on for any num ber of years. RULE. Find the interest for 1 year, and add it to the principal ; call this the amount for the first year. Find the interest of this amount and add it thereto for the amount of the second : and so on for any years. Subtract the original principal from the last amount, and the remainder will be the Compound Interest. EXAMPLES. 1. What is the amount, and what the compound interest, of $150 for 3 years, at per cent per annum? 6 6 =2d principal added. 6 (Carried over. ) 159, [Operation brought up.] 10,112400=interest. 168,54 $178,652400=amount for 3 years=$178 65cts. 2,4m. 150, =first principal subtracted. $ 28,652400=compound int. for 3yrs.= $28 65c. 2,4m. 2. What will $125 amount to in 4 years, at 6 per cent per annum, compound interest ? Ans. $157,80c. 9m+ 3. What is the compound interest of $750 for 5 years, at 5 per cent ? Ans. $207,21+ 4. What will be the amount of $410,50 for 3 years, at 6 Ans. $488,912+ 5. What is the compound interest of $500 for 3 years, at 6 per cent ? Ans. $95,50c. 8m. 6. What is the amount of $1000 for 4 years, at 6 per cent per annum, compound interest ? Ans. $1262, 47c. 6 2.m. + Note. When there are months, or months and days, in the question, first find the amount for the years, and on that amount calculate the interest for the months, or months and days ; this interest added to the amount for the years will give the amount required. 7. What will $148,25 amount to in 3 years and 6 months, at 6 per cent? Ans. $181,865+ 8. What is the compound interest of $500 for 4 years 2 months and 15 days, at 5 per cent ? Ans. $114,08+ per cent? BY DECIMALS. RULE. Multiply the principal continually by the amount of $1 or £1 for one year, at the given rate per cent, until the number of multiplications is equal to the given number of years. Thus, at 5 per cent, the amount for 1 year is 1,05 ; at 6 per cent, it is 1,06, &c. 1. What will be the amount of $500 for 3 years, at 6 per cent per annum ? Thus, 500 X 1,06 X 1,06 X 1,06=$595,508, Ans. Or, find the amount of $1, for 3 years, at 6 per cent per annum, 1,06 amount for 1 year. Note. Since the amount 1,06 of 2 dols. will be just twice 636 as much as 1 dollar, and 3 106 dollars 3 times as much as I 1,1236 amount for 2 yrs. that if we multiply the amount dollar, and so on, it is evident 1,06 of $1 by any given number of 67416 dollars, we have the amount 11236 for that number of dollars. 1,191016 amount for 3 yrs. Thus, the amount of $1 for 3 years, at 6 per cent, is 1,191016; this, multiplied by $500, gives the amount $595,508, the same as in example 1st. Hence we may have a Table showing the amount of £1 or $1, for any number of years, by which we inay easily find the amount of any snm for the same time, by multiplying the amount taken from the Table by the given sum. A TABLE, Showing the amount of $1, or £1, for any number of years, not exceeding 20, at 5 and 6 per cent, Compound Interest. YEARS. 15 PER CENT.) 6 PER CENT. YEARS. 5 PER CENT. 6 PER CENT. 1 1,05 1,06 11 1,71034 1,89829 1,1025 1,1236 12 1,79585 2,01219 3 1,15762 1,19101 13 1,88565 2,13292 4 1,21550 1,26247 1,97993 2,26090 5 1,27628 1,33822 15 2,07893 2,39655 6 1,34009 1,41851 16 2,18287 2,54727 7 1,40710 1,50363 17 2,29201 2,69277 8 1,47745 1,59384 18 2,40661 2,85433 9 1,55132 1,68947 19 2,52695 3,02559 10 1,62889 1,79084 20 2,65329 | 3,20713 3. What is the amouut, and what the Compound Interest, of $350 for 5 years, at 6 per cent ? Am't of $1 for 5yrs. at 6 per cent, by the Table 1,33822 Multiply by the principal, X 350 6691100 401466 Answer. Amount for 5 years, 468,37700 Subtract the principal, 350 Leaves the Compound Interest, $118,377 14 4. What is the amount, and what the Compound Interest of $311,25 for 6 years, at 5 per cent ? Ans. $417,103 Amount. $105,85,3 Compound Interest. [The learner may work all the preceding examples in Compound Interest by the foregoing Table of Amounts, if necessary for further practice.] Note. Any sum at 6 per cent, Simple Interest will double itself in 16 years 8 months; and at Compound Interest, in 11 years 8 months and 22 days. Questions, What does the term per centum, or What concise Rule have we for calckper cent, signify ? lating interest for New York State ? What is Interest? What is Commission ?-Brokerage ? What is the Rate of interest, establish- Insurance ?--Stock? ed by law in the New England States ? When is Stock said to be at par? What is the lawful interest in New When above par ? When below par? York State ? When the rate per cent is expressed in What is the Principal? - Rate? a Decimal Fraction, what is it called ? Amount? Havinng the amount time and rate per What is Simple Interest! cent given, how do you find the principal? How do you find the interest of any Having the amount, principal and time sum for 1 year? given, how do you find the rate per cent? What is the general Rule for calcula Having the principal, rate per cent and ting interest for any number of years, amount given, how do you find the time? months, &c. ? How do you compute the interest on How do you find the interest of any Notes, or obligations where endorsesum for any number of months at 6 per ments have been made ? cent? What is Compound Interest? How do you calculate interest for What is the Rule for Compound Intermonths and days, at 6 per cent ? est? DISCOUNT Is an allowance made for the payment of any sum of money before it becomes due. After the discount is de. ducted, the remainder is the present worth ; or, such a sum as, if put at interest, at the given rate and time, would amount to the given sum. RULE. 1. As the amount of $100, or £100, at the given rate and time, is to the interest of 100, at the same rate and time, so is the given sum to the discount. Subtract the discount from the given sum, and the remainder is the present worth. - Or by |