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FEDERAL MONEY.

II. To find the interest of any number of cents for any number of days less than a month, at 6 per cent.

RULE.

Multiply the cents by the number of days, divide the product by 6, and point off two figures to the right, and all the figures at the left hand of the dash, will be the interest in mills, nearly.

EXAMPLES.

Required the interest of 85 dellars, for 20 days.

$

cts.

858500X20-÷6-283,33

mills.

Ans. 283 which is 28cts. 3 mills.

2. What is the interest of 73 dollars 41 cents, or 7341 cents, for 27 days, at 6 per cent. ?

Ans. 330 mills, or 33cts.

III. When the principal is given in pounds, shillings, &c. New-England currency, to find the interest for any number of days, less than a month, in Federal Money.

RULE.

Multiply the shillings in the principal by the number of days, and divide the product by 36, the quotient will be the interest in mills, for the given time, nearly; omit ting fractions.

EXAMPLE.

Required the interest, in Federal Money, of 271. 15s. for 27 days, at 6 per cent.

£. S. S.

Ans. 27 15 555×27+36=416mills-41cts. 6m.

IV. When the principal is given in Federal Money, and you want the interest in shillings, pence, &c. New-Eng fand currency, for any number of days less than a

month.

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RULE.

Multiply the principal, in cents, by the number of days, and point off five figures to the right hand of the product, which will give the interest for the given time, in shillings and decimals of a shilling, very nearly.

EXAMPLES.

A note for 65 dollars, 31 cents, has been on interest 25 days; how much is the interest thereof, in New-England currency? s. d. grs.

Scis.

S.

Ans. 65,91 6531×25==1,63275=1 79 REMARKS. In the above, and likewise in the preceding practical Rules, (page 127) the interest is confined at six per cent. which admits of a variety of short methods of casting; and when the rate of interest is 7 per cent. as established in New-York, &c. you may first cast the mterest at 6 per cent. and add thereto one sixth of itself, and the sum will be the interest at 7 per cent, which perhaps, many times, will be found more convenient than the general rule of casting interest.

EXAMPLE.

Required the interest of 751. for 5 months at 7 per

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£. s. d.

37,5 1 17 6 for 5 months at 6 per cent.
+1= 6 3

Ans £2 3 9 for ditto at 7 per cent.

A SHORT METHOD FOR FINDING THE REBATE OF ANY GIVEN SUM, FOR MONTHS AND DAYS.

RULE.

Diminish the interest of the given sum for the time by its own interest, and this gives the Rebate very nearly.

EXAMPLES.

1. What is the rehate of 50 dollars for six months, at 6 nez cent

The interest of 50 dollars for 6 months, is
And, the interest of 1 dol. 50 cts. for 6 months, is

$ cts.

1

50

Ans. Rebate, $1 46

2. What is the rebate of 1501. for 7 months, at 5 per

cent. P

Interest of 150l. for 7 months, is

Interest of 41. 75. Gd. for 7 months, is

s. d.

47 6

2 61

Ans. 4 4 11

nearly.

By the above Rule, those who use interest tables in their counting-houses, have only to deduct the interest of the interest, and the remainder is the discount.

A concise Rule to reduce the currencies of the different States, where a dollar is an even number of shillings, to Federal Money.

RULE I

Bring the given sum into a decimal expression by in spection. (as in Problem I. page 87) then divide the whole by S in New-England and by,4 in New-York currency, and the quotient will be dollars, cents, &c.

EXAMPLES.

1. Reduce 54. Ss. 34d. New-England currency, to Federal Money.

,5)54,415 decimally expressed.

Ans. $181,58 cts.

2. Reduce 7s. 11d. New-England currency, to Federal Money.

7s. 11 d. 0,599 then, ,3),399

Ans. $1,35

3. Reduce 515. 16s. 10d. New-York, &c. currency

to Federal Money.

,4)513,842 decimal

Ans: $1284,60 ¿

4. Reduce 19s. 5d. New-York, &c. currency, to Fede. ral money.

,4)0,974 decimal of 19s. 5ąd.

82,434 Ans.

5. Reduce 641. New-England currency, to Federal Money.

,5)64000 decimal expression.

$215,334 Ans.

NOTE.-By the foregoing rule you may carry on the decimal to any degree of exactness; but in ordinary practice, the following Contraction may be useful.

RULE II.

To the shillings contained in the given sum, annex o times the given pence, increasing the product by 2; then divide the whole by the number of shillings contained in a dollar, and the quotient will be cents.

EXAMPLES.

1. Reduce 45s. 6d. New-England currency, to Feder

ral Money.

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Federal Money.

2. Reduce 2. 10s. 9d. New-York, &c. currency, t

9x8+2=74 to be annexed.

Then 8)5074

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Ans. 634 cents. 6 34

$6,34 Ans.

N. B. When there are no pence in the given sum, you must annex two cyphers to the shillings; then divide as before, &c.

3. Reduce 31. 5s. New-England currency, to Federal Money

sl. 5s. 65s. Then 6)6500

ents, 1083 Ans

200

SOMM USKRUL RULES,

YOR FINDING THE CONTENTS OF SUPERFICIES AND SOLIDS.

SECTION I. OF SUPERFICIES.

The superficies or area of any plane surface, is composed or made up of squares, either greater or less, according to the different measures by which the dimensions of the figure are taken or measured and because 12 inches in length make 1 foot of long measure, therefore, 12x12-144, the square inches in a superficial foot, &c.

ART. I. To find the arca of a square having equal sides.

RULE.

Multiply the side of the square into itself, and the product will be the area, or content.

EXAMPLES.

1. How many square feet of boards are contained in the floor of a room which is 20 feet square?

20x20-400 feet, the Answer. 2. Suppose a square lot of land measures 26 rods on rach side, how many acres doth it contain ? NOTE.-160 square rods make an acre.

Therefore, 26X26676 sq, rods, and 676-÷160-4a. $6r. the Answer.

ART. 2. To measure a Parallelogram, or long square.

RULE.

Multiply the length by the breadth, and the product will be the area or superficial content.

EXAMPLES.

1. A certain garden, in form of a long square, is 96 ft. long, and 54 wide; how many square feet of ground are contained in it ? Ans. 96x54-5184 square feet. 2. A lot of land, in form of a long square, is 120 rods in length, and 60 reds wide; how many acres are in it? 120×60 7200 sq. rods, then, 20045 acres, Ans. 3. If a board or plank be 21 feet long, and 18 inches broad; how many square feet are contained in it ?

7206

18 inches 1,5 feet, then 21X1,5=31,5 Ans.

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