Elementary arithmetic, with brief notices of its history... by Robert Potts.

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8. If a mixed metal be composed of 11 parts of tin to 100 parts of
copper, how much copper and how much tin will be required to make
24 cwt. of this metal?
9. Bronze contains 91 per cent. of copper, 6 of zinc, and 3 of tin.
A mass of bell-metal (consisting of copper and tin only) and bronze
fused together is found to contain 88 per cent. of copper, 4- of zinc,
and 7-I of tin. Find how much copper and how much tin are in bellmetal.
10. Sugar being composed of 491- per cent. of oxygen, 43Uo- per
cent. of carbon, and the remainder hydrogen, find how many pounds
of each of these materials are contained in 1121b. of sugar.
11. Sulphate of lime consists of oxygen 32 parts, sulphur 1 6- parts;
and calcium 20- parts; find the weight of each element in one pound
-of sulphate of lime.
12. In English gunpowder, 15 parts by weight are nitre, 2 parts
sulphur, and 3 parts charcoal. How many pounds of each ingredient
are required in making a ton of gunpowder?
XXII.
1. Multiply 7V- lineal inches by 57-, and by 5a- lineal inches respectively.
2. Multiply 73, square inches by 5 — lineal inches, and 5-T square
inches by 7-3 lineal inches.
3. Divide 7-3 square inches by 5-, by 5 - lineal inches, and by 5 -square inches respectively.
4. Divide 7:3 cubic inches by 57, by 57- lineal inches, by 57 square
inches, and by 57 cubic inches respectively.
5. Divide 3 lineal feet 8 inches by 1 lineal foot 10 inches.
6. Divide 8 square feet 48 inches by 3 lineal feet 4 inches.
7. Divide 3 cubic feet 192 inches by 18 square feet 48 inches.
8. Divide a cubic foot by 9, by 9 lineal inches, by 9 square inches
*and by 9 cubic inches respectively.
9. Explain if there be any difference between 301 square yards and
30} —yards square; and if any, how much.
10. Multiply and divide 52 feet 6 inches by 5 feet 10 inches, and
explain the results.
11. What length must be cut off a board which is 6- inches broad,
so that the area may contain a square foot?
12. How many superficial feet of inch plank can be sawn out of a
log of timber 20 feet 7 inches long, 1 foot 10 inches wide, and 1 foot 8
inches thick, supposing no waste in the sawing?
13. Of a field 5 is meadow, 38 is arable, and the remainder is
1 acre, 3 roods, 26 poles; find the quantities of meadow and arable
land.
14. A piece of land of 200 acres is to be divided among 4 persons in proportion to their rentals from surrounding property. Sup