Here I divide the amount of the grains by 24, to reduce them to penny-weights; the amount of the penny-weights by 20, to reduce them to ounces; and the amount of the ounces by 12, to reduce them to pounds.

PRACTICAL QUESTIONS.

1. Bought a Geography for 10 s. 6d.; an English Reader for 4s.; an Arithmetic for 4 s. 6d.; a slate for 2s. 8d., and a penknife for 2s. 9d.: what do they all amount to? Ans. 17. 4s. 5 d.

2. The national debt of England, at the Revolution, in 1689, was 10549257. 12s. 6d.; at the close of the American war, in 1783, it was 2382322477. 19s. 11d.; and in 1827 it amounted to about 9000000007. Required the sum of these several debts? Ans. 11392871737. 12s. 5d.

3. Bought 5 cheeses, weighing as follows; viz. the first cheese, 17 lb. 15oz.; the second, 22lb. 14oz.; the third, 191b; the fourth, 24lb. 7oz.; and the fifth, 21 lb. 12oz. Required the weight of the whole ? Ans. 106 lb.

4. A wall-maker built four stone walls for a farmer: the first wall was 94 rods, 12 feet, in length; the second, 42 rods, 10 feet; the third, 37 rods, 9 feet; and the fourth, 28 rods. What length of fence did the four walls make? Ans. 202 rods, 14 feet. 5. A landlord has 4 farms: the first contains 120 acres, 2 roods; the second 150 acres ; the third 215 acres, 1 rood, 28 square rods; and the fourth 96 acres, 2 roods, 22 square rods. How much land has he in all?

Ans. 582 A. 2R. 10sq. rd. 6. Bought three loads of wood: the first contained 124 cubic feet; the second 108cub. feet, 710 cub. inches; and the third 95 cub. ft. 1018 cub. in. Required the contents of all the loads? Ans. 2 cords, 72 cub. ft.

7. In the year 1820, there was raised in the county of Otsego, New-York, 125 bushels, 4 quarts, of Indian corn, on one acre; 120 bush. 2 pecks on another; 118 bush. 4 quarts on another; 117 bush. on another; 111 bush. on another; 95 bush. 4 quarts on another; and 90 bush. 2 pecks, 6 quarts, on another: how much on the seven acres?

Ans. 777 bush. 2 pk. 2 qt.

8. The periods of time in which the primary planets revolve round the Sun, and round their own axes, are as follows:

Is the subtraction of a less compound quantity, or number, from a greater of the same generic kind.

* RULE.

1. Set down the subtrahend, or less quantity, under the minuend, or greater quantity, in such a manner that those numbers which are of the same denomination may stand directly under each other, as in Compound Addition.

2. Beginning at the right hand, subtract successively, if possible, the lower number in each denomination from the upper, and write the remainder underneath; and the several remainders taken together will be the whole difference sought.

3. But if the lower number of any denomination be greater than the upper, borrow and add to the upper number as many of that denomination as make 1 of the next higher; then subtract the lower number from the upper one thus increased, and set down the remainder. Then carry 1, (as an equivalent to the number borrowed,) and add it to the next superior denomination in the lower quantity, and proceed as before.

*The reason of this Rule will easily appear from what was said in Simple Subtraction; for the borrowing depends upon the same principle, only the number borrowed is not always 10, as in Simple Subtraction, because the denominations of compound numbers do not all increase in a tenfold ratio.