If we would find the square feet in a floor 6 f. 4′ 8′′ in breadth, we proceed as follows.

length, and 4 f. 6′ 5′′ in

3

6 f. 4' 8"

4.

6' 5′′

We begin on the right hand, and multiply the whole multi

2′ 7′′ 11′′ 4′′ plicand, first by the seconds in

2' 4"

25 6' 8"

28 f. 11' 7" 11" 4"

the multiplier, then by the inches, and lastly by the feet. We then add the results together, and thus obtain the answer.

We are now led to a general rule for the multiplication of duodecimal numbers.

RULE. Place the several terms of the multiplier under the corresponding ones of the multiplicand. Beginning on the right hand, multiply the several terms of the multiplicand by the several terms of the multiplier successively, placing the right hand term of each of the partial products under its multiplier. Then add the partial products together; observing to carry one for every twelve, both in multiplying and adding. The sum of the partial · products will be the answer.

Questions in duodecimals are very commonly performed by commencing the multiplication with the highest denomination of the multiplier, and placing the partial products as in the first of the two following operations. The result is the same, whichever method is adopted. The second operation, however, is according to the rule we have given, and is more conformable to the multiplication of numbers accompanied by decimals.

When there are not feet in both the factors, there may not be any feet in the product; but, after what has been said, there will be no difficulty in determining the places of the product.

1. Multiply 14f. 9' by 4f. 6'.

2. What are the contents of a marble slab, whose length is 5f. 7', and breadth 1 f. 10'?

3. How many square feet are there in the floor of a hall, 48f. 6' long, and 24 f. 3′ wide?

4. Multiply 4f. 7′ 8′′ by 9f. 6'.

5. How many square feet are there in a house lot, 43 f. 3' in length, and 25 f. 6′ in breadth?

6. What is the product of 10f. 4′ 5′′ by 7f. 8′ 6′′? 7. Calculate the square feet in an alley 44 f. 2′ 9′′ long, and 2f. 10′ 3′′ 2′′′′ 4′′′′ wide.

8. How many square feet are there in a garden, 39 f. 10 7" long, and 18 f. 8' 4" wide?

9. What is the product of 24f. 10′ 8′′ 7" 5" by 9f. 4' 6"?

10. Compute the solid feet in a wall, 53 f. 6' long, 12f. 3' high, and 2f. thick.

11. The length of a room is 20 feet, its breadth 14 feet 6', and its height 10f. 4'. How many yards of painting are there in its walls, deducting a fire place of 4f. by 4f. 4'; and two windows, each 6f. by 3f. 2?

12. How many yards of carpeting, yard wide, will be required for a room 21 f. 6' long, and 18 f. wide?

13. What will the plastering of a ceiling come to, at 10 cents a square yard, supposing the length 21 feet 8 inches, and the breadth 14 feet 10 inches?

14. How many yards of papering on the four walls of a hall, 58 f. 8' long, 21 f. 4' wide, and 13 f. 9 high; de- ducting 2 doors, each 7 f. 6′ high and 4 f. wide; 7 windows, each 6 f. 2′ high and 3f. 10' wide; and a mop-board, 9 inches wide around the hall?

END OF PART SECOND.

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