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Percentage.

225. MISCELLANEOUS PROBLEMS.

1. Find 1% of 632; of 356; of 272.
2. Find 1% of 632; of 356; of 272.
3. Find .25%† of 632; of 356; of 272.
(a) Find the sum of the nine results.

4. Find 31% of 496; of 532; of 720.
5. Find 43% of 496; of 532; of 720.
6. Find 1.75% of 496; of 532; of 720.
(b) Find the sum of the nine results.

7. What part of 94 is 11?
8. What part of 94 is 36?
9. What part of 94 is 47?
(c) Find the sum of the three

What per cent ? What per cent? What per cent?

"

per cents."

10. 15 is 3% of what number? 11. 24 is 3% of what number?

4%?

5% ?

4%?

5% ?

4%?

5% ?

12. 42 is 3% of what number?
(d) Find the sum of the nine answers.

13. 375 is 125% (125) of what number?
14. 436 is 109% (188) of what number?
15. 598 is 115% (115) of what number?
(e) Find the sum of the three answers.

16. 544 is 15% less than what number?
17. 545 is 25% more than what number?
18. 510 is 170% of what number?
(f) Find the sum of the three answers.

*This means of 1 per cent.

†This means find 25 hundredths of 1 per cent.

Answer with a common fraction in its lowest terms.

Algebra.

226. TO FIND TWO NUMBERS WHEN THEIR SUM AND DIFFERENCE ARE GIVEN.

1. The difference of two numbers is 4 and their sum is 20. What are the numbers?

Let

then

x the smaller number,

x+4= the larger number,

and x+x+4= 20.

Transposing, x + x = 20 - 4.

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2. The difference of two numbers is 9 and their sum is 119.

What are the numbers ?

3. The difference of two fractions is and their sum is 4. What are the fractions?

3

4. The difference of two numbers is d and their sum is s. What are the numbers?

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Observe that any number you please may be put in the place of s, and any number less than s in the place of d; so when the sum and the difference of two numbers are given, the smaller number may be found by subtracting the difference from the sum and dividing the remainder by 2.

Algebra.

227. ANOTHER METHOD OF FINDING Two NUMBERS WHEN THEIR SUM AND DIFFERENCE ARE GIVEN.

1. The difference of two numbers is 17 and their sum is 69. What are the numbers ?

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2. The difference of two numbers is 8.4 and their sum 75.6. What are the numbers?

3. The difference of two numbers is d and their sum is s. What are the numbers?

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Observe that any number you please may be put in the place of s, and any number less than s in the place of d; so when the sum and difference of two numbers are given, the larger may be found by adding the difference to the sum and dividing the amount by 2.

4. A horse and a harness together are worth $146, and the horse is worth $74 more than the harness.

value of each.

Find the

Geometry.

228. HOW MANY DEGREES IN EACH ANGLE OF A REGULAR

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2. The sum of the angles of one triangle is equal to right angles; then the sum of the angles of 5 triangles is equal to

right angles.

3. But the sum of the central angles in figure 2, (a+b+ c+d+e) is equal to right angles; then the sum of all the other angles of the five triangles is equal to 10 right angles, less 4 right angles, or 6 right angles = 540°. But the angular space that measures 540°, as shown in figure 2, is made up of 10 equal angles, so each one of the angles is 1 tenth of 540° or 54°. Two of these angles, as 1 and 2, make one of the angles of the pentagon; therefore each angle of the pentagon measures 2 times 54° or 108°.

4. Using the protractor construct a regular pentagon as follows:

(a) Draw two lines that meet in a point, each line being 2 inches long and the angular space between them being 108°.

(b) Regarding the two lines as two sides of a regular pentagon, draw two more sides each 2 inches long and joining those already drawn at an angle of 108°.

(c) Complete the figure by drawing the fifth side, and prove your work by measuring the last line drawn and the other two angles.

229. Miscellaneous Review.

Remembering that in speaking of the per cent of loss or gain, the cost is the base unless otherwise specified, tell the per cent of loss or gain in each of the following:

1. Bought for 2 and sold for 3.
2. Bought for 3 and sold for 2.

3. Bought for 4 and sold for 5.
4. Bought for 5 and sold for 4.
5. Bought for 5 and sold for 6.
6. Bought for 6 and sold for 5.

7. Bought for 8 and sold for 10; for 12. 8. Bought for 8 and sold for 14; for 16. 9. Bought for 8 and sold for 18; for 20. 10. Bought for 8 and sold for 4; for 2.

11. Mr. Parker sold goods at a profit of 25%; the amount of his sales on a certain day was $24.60. How much was his profit?

12. Mr. Jewell sold goods at a loss of 25%; the amount of his sales on a certain day was $24.60. How much was his loss.

13. By selling a horse for $156 there was a loss to the seller of 20%. What would have been his gain per cent if he had sold the horse for $234?

14. A bill was made for wood that was supposed to be 4 feet long. It was afterwards found to be only 46 inches long. What % should be deducted from the bill?

15. The marked price on a pair of boots was 25% above cost. If the dealer sells them for 25% less than the marked price will he receive more or less than the cost of the boots?

16. If by selling goods at a profit of 12% a man gains $6.60, what was the cost of the goods?

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