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Denominate Numbers—Weight.

349. The standard unit of weight in common use is a pound Avoirdupois.

AVOIRDUPOIS WEIGHT.

16 ounces (oz.) 1 pound (1b.).

2000 pounds =1 ton (T.). The abbreviation for 1 hundredweight (100 lb ) is cwt.

MISCELLANEOUS WEIGHTS.

=

1 gallon of water
1 gallon of milk
1 gallon of kerosene
1 cubic foot of water
1 bushel of wheat
1 bushel of beans
1 bushel of clover seed
1 bushel of potatoes
1 bushel of shelled corn
1 bushel of ear corn
1 bushel of rye
1 bushel of barley
1 bushel. of oats
1 barrel of flour
1 barrel of beef or pork

about 8} 1b.
about 8 6 lb.
about 61 lb.

624 lb.
= 60 lb.
60 lb.
60 lb.
: 60 lb.
: 56 lb.

70 1b.*
- 56 lb.
48 lb.
32 lb.
- 196 1b.
= 200 lb.

PROBLEMS.

Find the cost
1. Of 2650 lb. coal at $5.50

per

ton. 2. Of 2650 lb. oats at 24¢ a bushel. 3. Of 3330 lb. wheat at 80¢ a bushel. 4. Of 4650 lb. potatoes at 42¢ a bushel.

(a) Find the sum of the four results.

*This means the amount of ear corn required to make 1 bushel of shelled

corn.

Denominate Numbers-Weight.

PROBLEMS.
Find the cost-

1. Of 2560 lb. hay at $7.50 per ton.
2. Of 1430 lb. straw at 30¢ per cwt.
3. Of 24 tons meal at of a cent a pound.
4. Of 11 tons corn husks at 14 cents a pound.
5. Of 3420 lb. hay at $8.00 per ton.

(a) Find the sum of the five results.

Find the cost

6. Of 2140 lb. oats at 24¢ a bushel.
7. Of 2140 lb. corn at 28¢ a bus el.
8. Of 2140 lb. wheat at 90¢ a bushel.
9. Of 2140 lb. barley at 364 a bushel.
10. Of 2140 lb. rye at 42¢ a bushel.

(b) Find the sum of the five results.

Find the cost

11. Of 520 lb. clover seed at $6.30 a bushes.
12. Of 520 lb. potatoes at 75¢ a bushel.
13. Of 520 lb. beans at $2.15 a bushel.
14. Of 520 lb. corn at 20¢ a bushel.
15. Of 520 lb. ear corn at 35¢ a bushe.

(c) Find the sum of the five results.

Find the approximate weight

16. Of a barrel of kerosene.
17. Of 1 quart of milk.

18. Of the oats that will fill a bin that is 4 ft. by 4 ft by 9 ft.

19. Of the water that will fill a tank that is 2 ft. by 2 ft. by 12 ft.

20. Of a five-gallon can of kerosene.

Denominate Numbers- Weight.

350. Troy weight is used in weighing gold, silver, and jewels.

TROY WEIGHT.

24 grains (gr.) = 1 pennyweight (pwt.).
20 pennyweights 1 ounce (oz.).
12 ounces

1 pound (lb.).

351. Apothecaries' weight is used in mixing medicines and in selling them at retail.

APOTHECARIES' WEIGHT.

20 grains (gr.)= 1 scruple (O).
3 scruples 1 dram (3).
8 drams

1 ounce (3).
12 ounces = 1 pound (th).

NOTE 1.—The pound Troy and the pound Apothecary are equal, each weighing 5760 grains. The pound Avoirdupois weighs 7000 Troy or Apothecary grains.

NOTE 2.—The ounce Troy and the ounce Apothecary are each 480 grains; the ounce A voirdupois is 437į grains.

QUERY.—Which is heavier, a pound of feathers or a pound of gold? An ounce of feathers or an ounce of gold?

PROBLEMS

1. Change 5 lb. Avoirdupois weight to pounds, ounces, etc., Apothecaries' weight. 2. How

many

5 gr. powders can be made from one Avoirdupois ounce of quinine?

3. One Avoirdupois ton of gold is how many Troy pounds?

4. Twenty-four Troy pounds equal how many Avo!rdupois pounds?

[blocks in formation]

So teach us to number our days that we may apply our hearts unto wisdom.

SHORT METHODS

IN

MULTIPLICATION AND

DIVISION.

Art. 1. To multiply a number by 50: Multiply of the number by 100. Why?

46 x 50 1 of 46 x 100 = 2300
47 x 50 3 of 47 x 100 = 2350

Multiply:
44 by 50 32 by 50 35 by 50
36 by 50 38 by 50 27 by 50
64 by 50 42 by 50 55 by 50

82 by 50 76 by 50 43 by 50
(a) Find the sum of the twelve products.

Art. 2. To multiply a number by 51: Take 50 times the number, to which add the number itself. Why?

48 x 51 50 times 48 = 2400 2400 +48 = 2448
37 x 51 50 times 37 = 1850 1850 + 37 = 1887

Multiply:
26 by 51 34 by 51 35 by 51
46 by 51 32 by 51 29 by 51
24 by 51 42 by 51 43 by 51

66 by 51 84 by 51 33 by 51
(b) Find the sum of the twelve products.

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