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1. Required the interest of 316 dollars for 1 year and 10 months. 11-half the number of mo.

Ans. 3476cts.=$34, 76cts.

2. What is the interest of 364 dols. 25cts. for 4 months?

$ cts.

364, 25

2 half the months.

728, 50cts. Ans.87, 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.


Multiply the given principal by ,08 and the product will be the interest for one month, in shillings and decimal parts of a shilling.


1. What is the interest of 325 dols. for 11 months?


9,75 shil. int. for 1 month.

X11 months.

Ans. 107,25s.£5 7s. 8d.

2. What is the interest in New-England currency, of 31 dols. 68 cts. for 5 months ?

Principal $1,68 dols.


,9504 Interest for one month.

Ans. 4,7520s. =4s. 9d.




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.


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.


1. A note for £411 New-England currency has been on interest one nionth; how much is the interest thereof in federal money?

£. 411

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Ditto for 7 months, 465,5cis. 84, 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.


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.


1 What is the interest of 21. 5s. for a year at 6 per ct.♪
£2 5s. 45s. Interest 45cts. the Answer.
2. Required the interest of 100%. for a year at 6 per ct.?
£100-2000s. Interest 2000cts.=$20 `Ans.

s. Of 27s. 6d. for a year?

Ans. 27s. is 27cts. and 6d. is 5 mills. 4. Required the interest of 51. 10s. 11d. for a year P! £5 10s. 110s. Interest 110cts.=$1,, 10cts. Om. 11 pence-2 per rule leaves 9


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

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

2. Cast the interest on the several payments, from the time they were paid, to the time of settlement, and find their amount; and lastly deduct the amount of the several payments, from the amount of the principal.


Suppose a bond or note dated April 17, 1793, was given for 675 dollars, interest at 6 per cent. and there were payments indorsed upon it as follows, viz. First payment, 148 dollars, May 7, 1794. Second payment, 341 dols. August 17, 1796. Third payment, 99 dols. Jan. 2, 1798. I demand how much remains due on said note, the 17th of June, 1798 ? $ cts.

148, 00 first payment, May 7, 1794.

Fr. mo

36, 50 interest up to-June 17, 1798.=4

184, 50 amount.


341, 00 second payment, Aug. 17, 1796. Fr. mo.
37, 51 Interest to June 17 1798. 1 10

$78, 51 amount.

[Carried over.

$ cts.

99, 00 third payment, January 2, 1798.
2, 72 Interest to-June 17, 1798.—5mo.

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675, 00 note, dated April 17, 1793.



209, 25 Interest to-June 17, 1798. 5 2

884, 25 amount of the note.
664, 73 amount 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 cent. which I received back in the following partial payments, as under, viz. 1st of April, 1796 16th of July, 1797 1st of Sept.


$ 50



How stands the balance between us, on the 16th November, 1800 ?

Ans. due to me $63, 18cts.


£62 10s. New-London, April 4, 1797. On demand I promise to pay Timothy Careful, sixtytwo pounds, ten shillings, and interest at 6 per cent. per annum, till paid; value received.



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tember 4, 1799.

And payment June 4, 1800,

1st. Received in part of the above note, Sep

How much remains due on said note. the fourth day of

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50 0

12 10

December, 1800 ?

£ s. d. 12 6


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, com→ pletely 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 160 dols. the amount of the debt, leaves in favor of the creditor, $89, 40 cts. or $10, 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 by decimals, page 175.

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