18 lb.-No. 2, 7 cwt. 0 qr.. 10 lb.-No. 3, 5 cwt. 3 qr. 26 lb.-No. 4, 8 cwt. 0 qr. 3 lb.; tare, 12 lb. per cwt.?

Ans. {Neat, 25cwt. Oqr. 1lb. Value, $93 78cts. 3m.+ 4. What is the cost of 24 casks of prunes, each cask weighing 1 cwt. 1 qr. 23 lb. gross; tare, 18 lb. per cask; Neat, 31cwt. Oqr. 8lb. Ans. Value, $160 79cts. 4m.

at $5.17 per cwt.?

5. Bought 15 boxes of sugar, each box weighing 1 cwt. 1 qr. 13 lb. gross; tare, 22 lb. per box: what was the neat weight, and amount at $9.64 per cwt.?

S Neat, 17cwt. 2qr. 5m..

Ans. Value, $169 13cts.+

6. What is the neat weight and value of 10 hogsheads of sugar, each hogshead weighing 6 cwt. 2 qr. 14 lb. gross; tare, 18 lb. per cwt.; tret, 4 lb. per 104 lb.; at 11 cents per lb. ? Neat, 53cwt. 1qr. 25lb. Value, $688 73cts. 5m.

Ans.

INTEREST.

INTEREST is an allowance made for the use of money. In computing interest, four things are to be particularly observed; viz principal, time, rate per cent., and

amount.

Principal is the sum for which interest is to be computed.

Rate per cent. per annum is the interest of 100 dollars or pounds for one year.

Time is the number of years, months, &c. for which interest is to be computed.

Amount is the principal and interest added together.

CASE 1.

When the time is one year, and the rate per cent. is any number of dollars or pounds.

Rule.-Multiply the dollars or pounds by the rate per cent., and divide by 100; the quotient will be the interest for one year.

Note. When the rate per cent. is not equal to a whole number, but consists of a fraction, such as 4, 4, or 3, the aliquot parts of the principal must be taken; after which, divide by 100 for the interest.

Note 2.-When the rate per cent. is any number of dollars or pounds, and 4, 4, or 4, say 44, 412, or 44 per cent., multiply the principal by the whole number, and add, 4, 4, or of the principal to the product, then divide by 100 as before.

Case 2.

When the interest is required for several years.

Rule. Find the interest for one year, and multiply the interest for one year by the number of years for which the interest is required.

Note. If the interest is required for years and months, multiply the interest for 1 year by the number of years, and add aliquot parts for the months of the interest for 1 year.

Case 3.

When the interest is required for any number of months, weeks, or days, less or more than one year.

Rule.-1. Find the interest of the given sum for 1

year.

2. Then, as 1 year is to the given time, so is the interest of the given sum for 1 year to the interest for the time required.

Case 4.

To find the interest of any sum for any number of days, as computed at banks.

Rule 1.-Multiply the dollars by the number of days, and divide by 6; the quotient will be the answer in mills. Rule 2.-The interest of any number of dollars for 60 days, at 6 per cent., will be exactly the number of cents; and if any other rate per cent. is required, take aliquot parts, and add or subtract according as the rate per cent. is more or less than 6.

Case 5.

The amount, time, and rate per cent. given, to find the principal.

Rule.1. Find the amount of 100 dollars for the time required, at the given rate per cent.

2. Then, as the amount of 100 dollars for the time required, at the given rate per cent., is to the amount given, so is 100 dollars to the principal required.

Case 6.

The principal, amount, and time given, to find the rate per cent.

Rule.-1. Find the interest for the whole time given, by subtracting the principal from the amount.

2. Then, as the principal is to 100 dollars, so is the interest of the principal for the given time, to the interest of 100 dollars for the same time.

3. Divide the interest last found by the time, and the quotient will be the rate per cent.

Case 7.

To find the time, when the principal, amount, and rate per cent. are given.

Rule-Divide the whole interest by the interest of the principal for one year, and the quotient will be the time required.

COMPOUND INTEREST.

Compound interest is that in which the interest for one year is added to the principal, and that amount is the principal for the second year; and so on for any number of years.

Rule.-1. Find the amount of the given sum for the first year by simple interest, which will be the principal for the second year; then find the amount of the principal for the second year for the principal for the third year; and so on for any number of years.

2. Subtract the first principal from the amount, and the remainder will be the compound interest required.

What is interest?

Questions.

What four things are to be particularly observed in computing interest?

What is principal'

What is rate per cent.?

What is time?

What is amount?

Repeat the rule for finding the interest, when the time is one year, and the rate per cent. is any number of dollars or pounds.

What is to be noted when the rate per cent. is less than a whole number, but consists of a fraction, such as ,, or ?

11

What is to be noted when the rate per cent. is any number of dollars, with a fraction; say 41, 41, 42, or the like?

How do you proceed when the interest for several years is required?

What is to be noted if the interest is required for years and months?

When the interest is required for any number of weeks or days, less or more than one year, by what rule do you perform the operation?

How do you proceed to find the interest, at 6 per cent., for any number of days, as computed at banks?

What is to be observed when the interest is at any other rate than 6 per cent.?

Repeat the rule to find the principal, when the amount, time, and rate per cent. are given?

How do you proceed, when the principal, amount, and time are given, to find the rate per cent.?

How do you find the time, when the principal, amount, and rate per cent. are given?

What is compound interest?

How is compound interest computed?

Examples in Case 1,

1. What is the interest of 500 dollars for 1 year, at 6 per cent. per annum?

100-$3000 Ans.

2. What is the interest of 225 dollars for 1 year, at 7 dollars per cent. per annum? Ans. $15.75. 3. What is the interest of 384 dollars 50 cents, for 1 year, at. 5 dollars per cent. per annum? Ans. $19.223. 4. What is the interest of £580 10s. for 1 year, at £6 per cent. per annum? Ans. £34 16s. 7d.

5. What is the interest of 1654 dollars 81 cents for 1 year, at 5 dollars per cent. per annum? Ans. $82.74.+ 6. What is the interest of 1500 dollars, for 1 year, at dollar per cent. per annum? Ans. $7.50.

7. What is the interest of £350, at 51 per cent. per annum, for 1 year? Ans. £18 7s. 6d.

8. What is the interest of 524 dollars, for 1 year, at 5 dollars per cent. per annum?

Ans. $27.51. 9. What would be the interest of 842 dollars, for 1 year, at 5 dollars per cent. per annum? Ans. $46.31.

Case 2.

1. What is the interest of 500 dollars, for 4 6 dollars per cent. per annum?

years, at

$500

6

30 00

4

$120 00 Ans.

2. What will be the interest of 540 dollars, for 2 years, at 5 dollars per cent. per annum? Ans. $54.00 3. What is the interest of £124 58. 6d. for 3 years, at £4 per cent. per annum? Ans. £14 18s. 3d.

4. What would be the interest of 482 dollars, for 7 years, at 6 dols. per cent. per annum? Ans. $202. 44.

Case 3.

1. What is the interest of £560, for 2 years and 6 months, at £5 per cent. per annum?