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as much in 8 days as he can earn in 12 days. If he can earn $21 in 12 days, in 8 days he can earn

18. Fifteen is

earn

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and

dollars.

times 6. A man can

times as much in 15 days as he can earn in 6 days. If he can earn $10 in 6 days, in 15 days he can

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(a) If a man can earn $104 in 6 weeks, how much can he earn in 15 weeks.

*It may be well, after the pupil has solved "mentally" such problems as Nos. 5 and 6, to require him to solve them with a pencil-this, as a preparation for similar problems in which larger numbers are used.

Allow the pupil to say, "15 is 3 halves of 10," but remind him that the expression "3 halves of 10," means, 3 times 1 half of 10.

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14. Henry had 25 cents; he spent 20 per cent of his money; he spent

cents.

15. Peter spent 10 cents; this was 25 per cent of all he earned; he earned

cents.

16. Roscoe earned 60 cents and spent 30 cents; he spent per cent of what he earned.

*TO THE TEACHER.-Frequently review this page, and give many similar oral problems as a preparation for page 27.

†These figures designate the percentage cases to which the problems below them belong.

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(m) 652 is 331% of what? (n) 6521 is 331% of what?

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11. One per cent (1%) of a number is 1 hundredth of

the number; 2% is 2 hundredths; 3% is 3 hundredths.

12. One per cent of 500 is

2% of 500 is

13. One per cent of 600 is

3% of 600 is

REVIEW.

1. Tell which of the following are odd numbers and which are even numbers: 14, 17, 19, 20, 24, 27.

2. The fractions, and have a

nator.

denomi

3. Change and to equivalent fractions having a common denominator. I can change thirds and fifths to

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5. Divide by 2. This means, find how many times

is contained in . I can change 5ths to One twentieth is contained in

twentieths

6. Multiply 6.05 by 3. Three times

(a) Find the product of 34.02 multiplied by 4.

10*

7. Divide $6.28 by 2. This means,
(b) Find the quotient of $475.65 divided by 5.

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=

20. times.

8. When hay is $12 a ton, 1500 lb. cost

9. When coal is $7 a ton, 3000 lb. cost

dollars.

dollars.

10. A 2-inch square is how many times as large as a 1-inch square?

11. A 2 inch cube is how many times as large as a 1-inch cube?

(c) How many square inches in an oblong 9 inches by 23 inches ?

12. Three fourths of 20 are 1 half of -.

(d) Three fourths of 84 are 1 half of what number?

*See note 10, page 9.

MISCELLANEOUS.

1. Mr. A owned 15 acres of land; he sold 64 acres ; then had

acres.

he

(a) Mr. B owned 546 acres of land; he sold 2284 acres How many acres had he remaining?

2. A bushel of oats weighs 32 lb.; 2 bushels of oats weigh pounds; 3 bushels weigh

pounds. (b) Sixty bushels of oats weigh how many pounds less than one ton?

3. Two pounds of coffee @ $.23 a pound cost

(c) Find the cost of 84 pounds of coffee @ $.23 a pound.*

4. From a piece of cloth containing 12 yards there were sold 5 yards and 2 yards; there were left yards. (d) From a piece of cloth containing 55 yards, there were sold 24g yd. and 173 yd. How many yards were left?

5. A boarding-school uses one gallon of milk each day;

at 54 a quart the milk for one week costs

(e) A boarding-school uses 4 gal. of milk each day; at 5¢ a quart how much will the milk for the month of October cost?

6. John bought 20 oranges at 34 each and sold them at 5¢ each; he gained

cents.

(f) John's father bought 25 bushels of potatoes at 32¢ a bushel and sold them at 45¢ a bushel. How much did he

gain?

$.23

84

*In multiplication of decimal fractions, require the pupil to locate the decimal point in the product immediately after he has written the figure to the right of the decimal point in any whole or partial product. Thus, in the multiplication of $.23 by 84 he writes (and thus locates) the decimal point of the product immediately after writing the figure 9 in the first partial product. This will be quite clear to the pupil if he understands that he first finds 4 times .23; then 80 times .23; then the sum of these two partial $19.32 products.

.92

18.4

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