55. A man can do a piece of work in 5 days, by working 8 hours a day; how many hours a day must he work to do it in 4 days?

56. If a certain amount of provisions will last 8 men 6 months, how long will it last 12 men?

57. If 9 men can build a wall in 5 days, how many men must be employed to build it in 3 days? 58. If it take 4 men 8 days to do a piece of work, how long will it take 16 men to do it?

59. How many men in 8 days can do a piece of work which will require 16 men 2 days to do?

60. If one pine-apple is worth as much as 2 oranges, and one orange is worth as much as 3 apples, how many apples are worth as much as 4 pine-apples?

ANALYSIS. If 1 pine-apple is worth 2 oranges, and 1 orange is worth 3 apples, then 2 oranges, or 1 pine-apple, will be worth 2 times 3 apples, which are 6 apples; and if 1 pine-apple is worth 6 apples, 4 pine-apples will be worth 4 times 6 apples, which are 24 apples.

61. If one horse is worth as much as 3 cows, and one cow is worth as much as 8 sheep, how many sheep are worth as much as 2 horses?

62. If one pound of sugar cost 3 times as much as a pound of flour, and a pound of flour cost 5 cents, how many cents will 4 pounds of sugar cost?

LESSON XVIII.

1. If 4 barrels of apples cost 8 dollars, what cost 5 barrels ?

ANALYSIS.

If 4 barrels of apples cost 8 dollars, 1 barrel will cost one fourth of 8 dollars, which is 2 dollars; and if 1 barrel of apples cost 2 dollars, 5 barrels will cost 5 times 2 dollars, which are 10 dollars.

2. If 3 pounds of butter cost 36 cents, what cost 5 pounds?

3. When 10 cents are paid for 5 rolls of candy, how much must be paid for 6 rolls?

4. When 5 dollars will buy 15 yards of cloth, how many yards will 9 dollars buy?

5. If 4 tons of hay cost 40 dollars, what cost 3 tons?

6. When 7 quarts of fruit bring 35 cents, how much do 5 quarts bring?

7. If 24 brooms cost 6 dollars, how many brooms can be bought for 8 dollars?

8. If 8 bushels of wheat cost 16 dollars, how much will 7 bushels cost?

9. What will 9 quarts of milk cost, if 10 quarts cost 50 cents?

10. If a horse trot 36 miles in 6 hours, how many miles will he trot in 11 hours?

11. What will 12 yards of broadcloth cost, if 15 yards cost 75 dollars?

12. If a man can earn 90 dollars in 9 weeks, how many dollars can he earn in 6 weeks?

13. If 3 pounds of cheese cost 30 cents, what will 6 pounds cost?

14. What cost 3 yards of cambric, if 6 yards cost 60 cents?

15. What cost 17 weeks' board, if 9 weeks' board cost 27 dollars?

16. What cost 4 tons of coal, at the rate of 10 tons for 70 dollars?

17. When 56 cents are paid for 4 dozen of eggs, how much must be paid for 10 dozen?

18. If 28 cents will buy 4 quarts of berries, how many quarts will 35 cents buy?

ANALYSIS. If 4 quarts of berries cost 28 cents, 1 quarr will cost one fourth of 28 cents, which is 7 cents; and if 7

cents will buy 1 quart of berries, 35 cents will buy as many quarts as 7 cents are contained times in 35 cents, which are 5. Therefore 5 quarts of berries can be bought for 35 cents, if 4 quarts cost 28 cents.

19. When 64 dollars are paid for 8 barrels of flour, how many barrels can be bought for 72 dollars? 20. How many pounds of veal can be bought for 96 cents, when 9 pounds cost 72 cents?

21. When 4 quarts of vinegar can be bought for 36 cents, how many quarts can be bought for 108 cents?

22. When 7 yards of cotton cloth can be bought for 84 cents, how many yards can be bought for 120 cents?

23. If 4 dollars will buy 32 yards of cotton cloth, how many dollars will buy 40 yards?

24. If 4 cents buy 8 apples, how much will 20 apples cost?

25. If 6 copies of a book cost 8 dollars, how much will 12 copies cost?

ANALYSIS. If 6 copies of a book cost 8 dollars, 12 copies will cost as many times 8 dollars as 6 copies are contained times in 12 copies, which are 2; therefore 12 copies will cost 2 times 8 dollars, which are 16 dollars.

26. If 3 hats cost 7 dollars, how much will 9 hats cost?

27. When 6 cents will buy 5 apples, how many apples will 60 cents buy?

28. How many oranges can be bought for 63 cents, at the rate of 4 for 9 cents?

29. If 4 cherries are worth as much as one plum, and 3 plums are worth as much as one peach, how many peaches are worth as much as 24 cherries?

NOTE. - Find, as in Example 60, Lesson XVII., that 1 peach is worth 12 cherries; then, if 12 cherries are worth 1 peach, 24 cherries will be worth as many peaches as 12 cherries are contained times in 24 cherries, which are 2.

30. If 2 bushels of oats are worth 1 bushel of corn, and 2 bushels of corn are worth 1 bushel of wheat, how many bushels of wheat are worth 20 bushels of oats?

31. What will 19 pounds of chalk cost, if 13 pounds cost 65 cents?

32. When wheat is sold at the rate of 6 bushels for 12 dollars, how many bushels must be given for 4 cords of wood, at 5 dollars a cord?

33. If 8 dozen of eggs are sold for 96 cents, how many dozen will it take to buy 6 yards of gingham, at 18 cents a yard?

34. A steamboat can run 8 miles an hour down river, and only 6 miles an hour up river; after running down river for 3 hours, how long will it be in returning?

35. A boat sailed up river for 10 hours, at the rate of 3 miles an hour, but returned over the same distance in 6 hours; how fast did it sail down stream? 36. If 12 barrels of flour cost 84 dollars, what will 7 barrels cost? 11 barrels ? 6 barrels ? 10 barrels ? 9 barrels ?

37. A man bought 12 bushels of wheat, at 2 dollars a bushel, and 4 yards of cloth, at 3 dollars a yard, and paid for them in work, at 9 dollars a week; how many weeks did he work?

38. If you should buy 60 pears, at the rate of 4 for 3 cents, and sell them at a cent apiece, how much would you make by the operation?

39. If 10 men can do a piece of work in 12 days, how many men must be employed to do it in 15 days? 40. When 7 cords of wood can be bought for 56 dollars, how many cords of wood can be bought for 72 dollars?

41. If 9 men can dig a ditch in 8 days, how long will it take 12 men to dig it?

42. How many books, at 6 dimes each, will 9 books, at 4 dimes each, pay for?

43. A can travel at the rate of 5 miles an hour, and B7 miles; they set out from the same point, and in the same direction, but B starts after A has traveled 30 miles; how long will it take B to overtake A?

44. William can run 40 rods in 5 minutes, and Jason the same distance in 4 minutes; how long will it take Jason to gain 30 rods on William?

45. Three men buy a horse, A paying 12 dollars, B paying twice as much as A, lacking 4 dollars, and C paying 28 dollars; what would have been the cost to each person, if the expense had been shared equally?

46. If 3 cords of wood are worth 18 dollars, and 10 cords are given for 12 thousand of shingles, how much are the shingles a thousand?

47. How much rye, at 9 dimes a bushel, must be given for 27 bushels of buckwheat, at 3 dimes a bushel?

48. If 3 pounds of flour are worth 1 pound of sugar, and 6 pounds of sugar are worth 1 pound of tea, how many pounds of flour are worth 2 pounds of tea?

49. If 6 men can reap a field in 4 days, in how many days can 8 men reap it?

50. When 3 pounds of cheese cost as much as 1 pound of butter, and 3 pounds of butter as much as 1 pound of tea, how many pounds of tea cost as much as 81 pounds of cheese?

51. If a cistern, capable of holding 60 gallons, has a pipe by which 10 gallons can run into it in one hour, and another pipe by which 5 gallons can run out of it in the same time, when both pipes are running, in what time will the cistern be filled?