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26. How many card cases, requiring square foot of leather, can be made from a pig skin, containing 4 square feet, not allowing for waste?

27. How many wrist purses, requiring is square feet of leather, can be made from the same sized skin?

28. Allowing á of a quart of cream apiece, how many children can be served with 3 quarts of ice cream?

29. Which will fill an exact number of sacks for a candy sale —to put 4 pounds of stuffed dates into bags holding pound or to put s pound into each sack?

30. Betty sent to a publishing house $4.00 which her class had paid to subscribe to a weekly newspaper. If each subscription was $}, how many copies of the paper were subscribed for?

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Exercise 30. Dividing a Fraction by a Fraction 1. What is 3 = ? 1st method. We can not divide 7 eighths by 3 fifths in the form in which they stand, so we first change them to fortieths.

= 5 and = 24
35 fortieths-24 fortieths=3 times, or 131.
2nd method. We found in Exercise 24 that 1:

1:35
Ž= will give { as great a quotient as 1=
Then 3 = = x - , or 111.

3 We see that the second method is much easier because it saves us the trouble of reducing both fractions to common denominator.

In dividing one fraction by another use the following:
PRINCIPLE: To divide a number by a fraction, invert the

divisor and multiply.

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35
24

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Divide: 1.

11. 19 = 1 21. Ž: 5 31. 1 = 2. ki 12. = 1 22. 1 32. 11-1 3. 1. - 3 13. k=1 23. 4: 33. = 3

14. 1+1 24. 4+4 34. = 5. 11: 16. : 4 26. + 36. 4:} 6.

16. 1 = 1 26. 1: 36. 18+ 7. = 5 17. 11: 27. 14:4 37. 18+ 8. 16 = 1 18. 1: 28. 16 = 1 38. %:11 9. 1:1 19. 15: 5 29. 6: 39. 10. 3 = 20. 16:} 30. 3+ 40. 18:11

41. Richard uses į pound chocolate in making a certain fudge recipe. How many such recipes of fudge should he be able to fill from a 3-pound cake of chocolate?

42. Three-fourths of a pound of shelled nuts are enough for how many small loaves of nut bread, each loaf requiring i pound of nuts?

43. It took { can of paint to finish each pair of tin book ends made in a certain handwork class. An opened can of paint

full should finish how many book ends?

44. Painted flower pots required only 1 can. This can i full should be enough to finish how many flower pots?

45. A remnant of leather containing of a square foot should be enough for how many wrist purses requiring 12 square foot? Allow it square foot waste for careless cutting.

46. Albert wished to buy 15 apples for a party. He asked the storekeeper to weigh an apple. They found a medium sized one to weigh pound. How many pounds must he buy to obtain 15 apples?

Exercise 31. Dividing by a Mixed Number

As we noted in the multiplication of mixed numbers, it was much easier to reduce the mixed number to an improper fraction and then treat it as a fraction, so in dividing by a mixed number it is easier to reduce the mixed number to an improper fraction and follow the principles for the division by a fraction (see page 80).

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1. Ethel's mother has made 84 quarts of apple jelly and has asked Ethel to get ready enough 1-pint glasses to hold it. How many were needed?

2. In order to get an exact number of rows in his garden,

should John set out sorá dozen cabbage plants to a row, there being 73 dozen plants in all?

3. How many ferns at $2 each can Dorothy buy for her fernery with $11?

4. If, during berry season, Carl earns on the average $13 a day, how many days must he work to earn $26 for a bicycle?

5. How many }-bushel baskets will 22 bushels of grapes fill?

6. How many tea towels, each requiring a ż-yard length, may be cut from a remnant of toweling 31 yards long?

7. A remnant of "honeycomb” cloth 22 yards long may be made into how many dish cloths requiring } yard each?

8. How many pans are needed to hold 32 dozen cookies at one baking, each pan holding dozen cookies?

9. How many 3-pound sacks will 21 pounds of blanched almonds fill?

10. Into how many in-hour periods can a 50,-hour school day be divided?

11. A group of girls together buy a 10-yard bolt of nainsook. How many aprons can they make from it if each apron requires 22 yards?

12. George and Helen found that they could make 4 quarts of lemonade for 25 cents. What was the cost of 1 quart?

13. Counting 4 glasses to a quart, find the cost of 1 glass.

14. How many holder covers 52 inches long can be cut from material a yard long and of the proper width? (1 yard = 36 inches.)

15. Marian and her mother, in dressing dolls for a bazaar, used a certain little dress pattern requiring yard of material. How many could they cut from a 2-yard remnant which Marian's mother had?

16. How many shelf boards 2 feet long can Richard cut from a 12-foot board of proper width?

17. How many picture postals at 22 cents a piece can one buy for a quarter?

18. Herman, who lived in the country, walked 6s miles a day in order to attend a city high school. At this rate, how long was it before he had walked a hundred miles?

19. A train averaging 45miles an hour should make a 500mile run in how many hours?

20. A boy who, in a trial speed test, correctly works 2 multiplication problems in 2 minutes should, at the same rate, be able to solve how many of equal difficulty in a final 6-minute test?

21. How many aprons requiring 2 yards each can be made from 167 yards of cloth?

22. The smaller girls in a sewing class found their smocks required 23 yards apiece. How many could be cut from a 121yard length of poplin?

23. Theodore decided to set the rows of his strawberry bed 31 feet apart. If the plot which he spaded for the bed was 172 feet wide, how many rows were there?

24. Jasper's garden is 73 yards long. Into how many plots 11 yards long can he divide it?

26. What is the average speed of a train which travels 933 yards in 23 hours?

26. How many times can 52 gallons of gasoline be drawn from a barrel that contains 31gallons?

27. A certain kind of barbed wire weighs 13 pounds per rod. How much does it weigh per foot? (16] feet = 1 rod.)

=) 28. At the rate of 2] miles an hour, how long would it take a squad of boy scouts to walk 122 miles?

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