Page images


2. .

1 What is the interest of 21. 55. for a year at 6 per ct. 2 55, -=45s. Interest 45cts. the insirer.

6 1("' =2000s. Interest 2000cis.=:8:20 Ans. 3. Or 75. C. fior it rear:

Ans. 37s. is 27cts, and 6d. is 5 :rills. 4. Required the interest of 5l. 10s. 111. for å rear :

:5 10s.110s. Interesi 110cts.=81, lets. Om 11 peioemper rule leuves 9=


[blocks in formation]


VI. 'To compute the interest on any note or obligation when there are payments in part, or indorsements.

RCLE. 1. Find the amount of tiie whole principal for the whole time.

2. Cast the interest in the several payments, from the time they were paid, to the time of settiement, and litid their amunt; and lastly cierluci the amount of thie seveal payments, froin the amount of the principal.

Suppose a bond or note viated April 17,1793, was given for 675 dollars, interest at 6 per cent. and there were payments indorsed upon it as follows, viz..

Forsi payınent. 148 dollars, May in 1734.
Second payment, 5+1 dols. August li, 1:36.

Third payment, 99 dols. Jan. 2, 1.98. Treniand how much remains due on said note, the 17th of June, 1798

.8 rts.
148, 00 first payment, May 7, 1794.
S6, 50 interest up to June 17, 1798.=

Fr. mo

181, 50 amount.

341, on second payment, Aug. 17, 1796. Pr. no. 3?, 51 Interesi i June 17 1798. 10

678, 51 amount.

Carried over.

99, 00 third payment, January 2, 1798.
2, 72 Interest to June 17, 1798.57m.

[blocks in formation]
[ocr errors]

67.5, 00 note, dated April 17, 1795.
209, 25 Interest to-June 17, 1798. x5

884, 25 amount of the note.
664, 73 ainount of payments.

$219, 52 remains due on the note, June 17, 1798. 2. On the 16th of January, 1795, I lent James Paywell 500 dollars, on interest at 6 per ceut. which I received back in the following partial payments, as under, viz. 1st of April, 1796

S 50 16th of July, 1797

400 1st of Sept. 1798

60 How stands the balance between us, on the 16th No vember, 1800 ?

Ars, due to me 863, 18cts. 3. A PROMIS6ORY NOTE, viz. $62 10s.

New-London, April 4, 1797. On demand I promise to pay Timothy Careful, sixtytwo pounds, ten shillings, and interest at 6 per cento per annum, till paid; value received. JOHN STANBY,


2. 1st. Received in part of the above note, September 4, 1799.

500 And payment June 4, 1800,

12 10 How much remains due on said note, the fourth day of December, 1800 ?


S. d.

NOTE.-The preceding Rule, by custom is rendered so popular, and so much. practised and esteemed by many on account of its being simple and concise, that I have given it a place: it may answer for short periods of time, but in a long course of years, it will be found to be very errone.


Although this method seems at first view to be upon the ground of simple interest, yet upon a little attention the following objection will be found most clearly to lie against it, viz. that the interest will, in a course of years, completely expunge, or as it may be said, eat up the debt. For an explanation of this, take the following


A lends B 100 dollars, at 6 per cent. interest, and takes his note of hand; B does no more than pay.

A at every year's end 6 dollars, (which is then justly due to B for the use of his money) and has it endorsed on his note. At the end of 10 years B takes up his note, and the sum he has to pay is reconed thus : The principal 100 dollars, on interest 10 years amounts to 160 dollars ; there are nine endorsements of 6 dollars each, upon which the debtor claims interest; one for 9 years, the second for 8 years, the third for 7 years, and so down to the time of settlement; the whole amount of the several endorsements and their interests, (as any one may see by casting it) is $70, 20 cts. this subtracted from 180 dols. the amount of the debt, leaves in favor of the creditor, 889,40 cts. or 810,20 cts. less than the original principal, of which he has not received a cent, but only its annual interest.

If the same note should lie 20 years in the same way B would owe but 37 dols. 60 cts. without paying the least fraction of the 100 dollars borrowed.

Extend it to 28 years, and A the creditor would fall in debt to B, without receiving a cent of the 100 dollars which he lent him. See a better Rule in Simple Interest ny decimals, page 175.

er year, est upon

COMPOUND INTEREST, Is when the interest is added to the principal, at the end ul the year, and on that amount the interest cast for anoth

and allied again, and so on : this is called Inter Interest.

RULE. Find the interest for a year, and acid it to the principal, which call the amount from the first vear ; find thic interes! of this amount, which add as belure, for the amount of the srcond, and so on for any number of years required. Sibtract the original prin ipal from the last amount, and the remainder will be the Compound Interest for the whole time.


1. Required the amount of :on dollars for 3 years at 6 per ceat. per ansiuni, compound interest i


8 ots. 1st Principal 100,00 Amount 106.00 for 1 gear. 2. Principal 106,00 Anouut 112,36 for years. Sd Principal 112,36 Amount 119.1010 for 3 yrs. Ans.

2. What is the amount of 125 dritars, fur 1 year's, at 5 per cent. per annuil, compound interest i

Ans. 8516, 59cts, s. What will 4001. annount to, in 4 years, at li per cent. per annum, compouni interest i udos: 6.5014 195. 93d.

4. What is the compound interest of 1501. 106. Boxe 3 years, at 6 per ct. per alltsum ? Hus. £28 14x, 111d. +

5. What is the compound interest of 500 dollars for 4 years, at 6 per cent. per annum: Axs. 8131.238+

6. What will 1000 dollars amount to in 4 years, at 7 per cent per annum, compound interest ?

Anx. 81310, 79c1s. 6m. + 7. What is the amount of :50 dollars für 4 years, at 6 per cent. per annuin, compound interest :

wdrs. 8946, 83eta. :,2m. 8. What is the compound interest of 876 Juli. 90 cta far 35 years, at 6 per cento per annuu?

ima 8198, dicta +

DISCOUNT, Is an allowance maile for the ravinent of any sum on money belore it becomes due; or upon advancing reals money for notes, bills, dic. which are payable at a mure day. Wai remains after the discount is lelucted, is rho: present wojtli, or such a sum ás, il pi tu interest would at the given rate anul time, amount to the given sum or debt.

RULE. As the amount of 100?. or 100 dollars, 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 sun, and the remainder is the present worth.

Oris the amount of 100 : is to 100 : : so is the given sum or debt : to the present worth.

Proor. Find the amourit of the present worth, at the given rate and time, and if the work is right, that will be equal to the given sum.

EXAMPLES. 1. What must be discounted for the ready payment of 100 dollars, due a year hence at 6 per cent. a year

8 $ 8

$ ots.
As 106 : 6 :: 100 : 5 66 the answer.

100,00 given suin.

5,66 discount.

$94,94 the present worth. 2. What sum in ready money will stischarge a debt of 9931. dlue 1 year and 8 months hence, at 6 per cent. i


19 Interest for 20 molithis.

110 Am't. £. £ fo

4. 6. d. As 110 100 :: 925 810 18 24.11s. 3. What is the present worth of 600 dollars, duc 4 years hence, at 5 per cent. :

ns. 6.300) 4. What is the discount of 275l. 10s. for 16) onths, at 6 per cent. per anuun? Ans. £13 2s. 4jch

« PreviousContinue »