A merchant bought 4 barrels of potash of the following weights, viz. 1st, 3 cwt. 1 gr. 25 lb. 12 oz. 3 dr.; 2d. 4 cwt. 1 qr. 21 lb. 4 oz.; 3d. 4 cwt.; 4th. 3 cwt. 3 qr. 27 lb. 15 oz. 15 dr.: What was the entire weight of the four barrels ?

Ans. 15 cwt. 3 qr. 19 lb. 0 oz. 2 dr.

There are 4 fields, the first contains 12 A. 2R. 38P.; the 2d. 4A. 1R. 26P.; the 3d. 85A. OR. 19P.; and the 4th. 57A. 1R. 2P.: how many acres in the four fields?

§ 95. Subtraction of denominate numbers teaches how to find the difference between two denominate numbers that are unequal.

RULE.

I. Set down the lesser number under the greater, placing the same denominations directly under each other.

II. Begin with the lowest denomination, and if the number expressing that denomination be less than the number directly over it, make the subtraction as in simple numbers. But if it be greater, subtract it from the upper number increased by so many units as make one unit of the next higher denomination, and

carry this one which has been borrowed to the next higher denomination, as in subtraction of simple numbers.

III. Do the same for all the denominations, and set down the several remainders, and they will form the true remainder.

In this example we cannot take 9d. from 8d.; we therefore add 12d. to the 8d. making 20d., and then say, 9 from 20, 11 remains. Set down the 11, and carry one to 17 making 18: then say 18 from 36 leaves 18: set it down and carry one to 19 making 20: 20 from 27 leaves 7.

Or we may set down the minuend as on the right: £26, 35s. 20d. Then 9 from 20 leaves 11; 17 from 35 leaves 18; and 19 from 26, 7 remains.

In this example, we take 26 from 48; then 3 from 3; then 18 from 32; then 3 from 4.

PROOF.

§ 96. Add the remainder to the subtrahend-their sum should be equal to the minuend.

QUESTIONS.

95. What is subtraction of denominate numbers? How write down the numbers for subtraction? Where do

to subtract? When the number to be subtracted

is less than the one above it, what do you do? When it is greater, what do you do?

§ 96. How do you prove subtraction ?

1. Sold a merchant one quarter of beef for £2 7s 9d; one cheese for 9s 7d; 20 bushels of corn for £4 10s 11d; and 40 bushels of wheat for £19 12s 8d how much did the whole come to?

Ans. £27 111d.

2. Bought of a silversmith a tea pot, weighing 3lb. 4oz. 9pwt. 21gr.; one dozen of silver spoons, weighing 2lb. 1oz. 1pwt.; 2 dishes weighing 167b. 10oz. 15pwt. 16gr.: how much did the whole weigh? Ans. 221b. 4oz. 6pwt. 13gr.

3. Bought one hogshead of sugar, weighing 9cwt. 2qr. 27lb. 14oz.; one barrel weighing 3cwt. 27lb., and a second barrel weighing 2cwt. 3qr. 26lb. 4oz.: how much did the whole weigh?

Ans. 15cwt. 3qr. 25lb. 20