6. A stere is a cubic meter. What will be the cost, at 8 f. 50 per stere, of a pile of wood 10 meters long, 1 meter wide, 3 m. 25 high?

7. A cube one decimeter each way contains a liter (1.), which is the principal unit of dry and liquid measure.

How many liters' capacity has a tank 10 m. 50 long, 8 m. wide, 6 m. 50 high?

8. How many bottles, each containing 0 1. 75, can be filled from a hogshead containing 222 1.?

9. How much will be received for 36 bags of beans, each containing 68 liters, at 1 mark 25 per dekaliter?

10. A liter of water weighs a kilogram (1,000 grams). How many kilos of oil would a tank contain, its dimensions being 5 meters x 4 meters x 3 meters, the weight of the oil being 92% of the weight of water?

11. Assuming the length of the meter as 39.37 inches, what is the length of the kilometer?

1185. Greater accuracy is assured in operations requiring multiplication and division by indicating the operations beforehand, and performing the division last.

12. Mt. Blanc is 4800 m. high. How many feet high is it?

1186. In the following ten problems call the meter 40 inches. Give answer in two decimal places.

13. How many cubic inches in a liter? (See problem 7.) How many quarts?

14. How many bushels in a hectoliter? How many gallons?

15. How many pounds in a kilo, when a cubic foot of water weighs 1,000 oz.? (See problem 10.)

16. What would be the circumference of the earth in miles if the meter measured 40 inches?

(The meter is rooooooo of what part of circumference?)

17. How many square yards in a square meter?

18. How many acres in a hectare? (See problem 4.)

19. How many rods in a hectometer?

20. How many cubic feet in a stere? (See problem 6.)

21. How many troy grains (7,000 to av. lb.) in a gram? (See problem 15.)

22. How many kilometers in a mile?

1188. The square meter is the principal unit of surfaces, such as walls, ceilings, floors, etc.

100 centiares (ca.) = 1 are (a.) = 119.6 sq. yd.

1189. The are is the principal unit of surface of small plots of land. The area of a farm is expressed in hectares, of a country in square kilo

1192. The stere (cubic meter) is used for measuring wood. 10 decisteres (dst.) = 1 stere (st.) = 35.316 cu. ft.

1194. The liter and the hectoliter are the principal units.

1196. The kilo is the ordinary unit. Heavy articles are sold by the

tonneau.

CHAPTER XV.

ALGEBRAIC EQUATIONS.-TWO UNKNOWN QUANTITIES.THREE UNKNOWN QUANTITIES.-PURE QUADRATICS.AFFECTED QUADRATICS.

1200. In the quantities 2a, 3x, 5 xy, 15 abc, the numbers 2, 3, 5, 15, are called coefficients. When no coefficient is expressed, 1 is understood. Thus, abc = 1 abc.

Where no sign is expressed, + is understood.

1201. What a person has may be represented with a plus sign (+) placed before the amount; debts may be shown by a minus sign (-) placed before the amount.

530

xy

6 abc

abc

?xy

? abc

A has $500; Bowes $300. If they unite their fortunes, what will they be worth together?

+$500

-$300

+$200

Both together are worth $200.

The sum of 500 and 300 is + 200.

1202. If A had $300 and B owed $500, the firm would be $200 in debt.

(+$300)+(-$500) = $200.

7 a

5x

2xy

abc

15 xyz

- 5 a

6 х

-?xy

?

?

1204. Can you give the rule for addition where the quantities have different signs? Which sign does the sum take?

1205. Add:

6. 3x+14,7x+9, 23, 4x-5, -2x, and 3x+11.

3x+14 -7x+9

- 23

4x-5

- 2x
3x+11

7. 4a+3x, 2a, -7x-3a, -5x, -9a+x.

8.3b+c, 4a+6b, 5b-9c, -3a, -2a-3b+4c.

9. x 8,-x+4, -4x-3, 7x+16, -5x-10. 1x8,

10. 4x+23, -8x+21, −x+11, − x+5, 9x - 3.