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15. If in a school of 360 children, 27 play truant, and 63 are sick, what percentage of non-attendance is due to truancy and to sickness respectively?

16. If the duty on an article be in 5 consecutive years 19'3, 20, 175, 231, and 18.6 p. c., what is the average yearly duty per cent.?

17. If 1185 parts of copper be added to 715 parts of tin and 100 parts of zinc, what is the percentage of each metal in the compound?

18. The population of a country amounts to 26,584,000, and increases at the rate of 10 p. c. in every 10 years; what will it amount to in 30 years?

19. If the population of the globe be eleven hundred millions of souls, and 3,300,000 of these be Jews, 172,700,000 Mahometans, 337,700,000 Christians, what is the percentage of each?

20. Between 1821 and 1831 the population of a certain town increased by 24 p. c., and in the last-named year amounted to 62,093; what was the population in 1821?

21. A grocer uses for a lb. weight one which weighs only 1575 ozs.; to what extent per cent. are his customers defrauded?

22. Find the percentage of alloy in sterling gold, if 10 dwt contain 21 grains of alloy.

23. What percentage of 89 is o56, and what percentage of the square root of '04 is the square of '19?

24. An army consists of a number of men equal to the Quotient of 72 by 0045; what percentage of men may be killed so as still to leave a number equal to the square root of 225 millions?

25. The annual consumption of meat in the United Kingdem being 33,697,785 cwt., what amount of saving would be effected to the community by a reduction of 24d. per lb., and what percentage would be saved by such reduction if we take the present average price of meat 91d. ?

26. A certain officer has a salary of £1250 per ann.; what is the salary of his chief clerk, which is 44 p. c. of his own? The junior clerk's salary is 78 p. c. of the senior's; what is the junior's salary per week?

27. In 1878 the number of deaths in a certain kingdom was 391,369; the decrease per cent. was 8.18103 from the preceding year: what was the number of deaths in 1877?

28. A cubic boiler half full of boiling water contains 500 cub. in. of steam; if the water be boiled down to a depth of only 298 in., what percentage of the cubical space of the boiler will be occupied by steam?

29. I bought 5 cwt. 3 qrs. 14 lbs. for £9, 8s., and sold them for £11, 18s. 11d.; what was the percentage of gain, and what the gain per cwt.?

30. (a) If 50 quarters of wheat sell for 77s. 8d. per quarter, and 100 quarters for 78s. 3d. per quarter, what is the average price per bushel?

(b) If the population of Great Britain in 1851 was 21,121,967, and the increase during the preceding half-century was 93'47 p. c., what was the population in 1801?

31. Out of 360 children in a mixed school, 29.16 p. c. are girls, 333 p. c. boys, and the remainder infants. On a certain day of each are present; how many boys, girls, and infants respectively are registered?

32. 5 per cent. on a given sum yields £377083; give 51 per cent. on half that sum in £ s. D.

33. If the ton be diminished 10.714285 per cent., and the ounce avoirdupois be increased 25 per cent., how many lbs. would there be in a ton?

34. John had 3s., and gave away 1d.; William had 4s. 8d., and gave away 31d.: how much more per cent. of his money did the latter give than the former?

35. People sometimes speak of an acre as 70 yards square. What percentage of error is involved in this assumption, and what amount of error would arise in calculating the area of Ireland (32,000 square miles)?

36. If pure gold is worth £4, 5s. per oz., and silver is worth 5s. 6d. an oz., what would be the weight of a 15s. piece, containing 92.5 per cent. of value pure gold, and the rest silver?

37. What would be the weight of the piece in the above question if '92.5 per cent. of weight' be substituted for '92.5 per cent. of value?'

38. A ship worth £8100 being entirely lost, of which belonged to A, to B, and the rest to C; what loss will each partner sustain, supposing the property to be insured up to 60 p. c. of its value?

39. If the population of a country increased from 2,800,000 to 3,500,000 in 3 years, what is the rate of increase p. c. per ann. ?

40. What percentage of 324 is the square root of that number?

41. What was the original population of an island, which was reduced 40 p. c. in 1 years by a plague carrying off 25 inhabitants on an average per week?

42. A sample of bone dressing was found to contain 15.83 per cent. of sulphate of lime. Find the weight of sulphate in 108 tons of dressing.

43. In 1851 the population of a certain kingdom had increased from 1841 at the rate of 73361818 p. c., and had reached 27,674,352; what was the population in 1841?

44. If a certain article weighing 24 cwt. contain 89 per cent. of copper and the remainder tin, what weight of tin does it contain?

45. A cask containing 2000 gallons of gin leaked to the extent of 27 per cent. ; how much gin remained in the cask?

46. Express in decimal form per cent., 2 per cent., and 5 per cent.

47. If out of a school of 150 children, 7 p. c. are up to Standard vi., and 11 p. c. up to Standard v., how many children are below these two standards?

48. Write in a decimal form 1, 1, 2, 3, and 41 per cent.

49. If iron ore produces 39 p. c. of pure metal, how much cre will be required to yield material for nine 35-ton guns, and 10,467 shells each weighing cwt.?

50. The population of a parish is 2000, of which 3 are males, *175 females, and the rest children. Find the number of each class, and the percentage of each class in the parish.

51. A town contains a population of 5005 persons, of whom

ought to be at school; if 819 only are present, what is the percentage of truants?

52. X, Y, and Z each laid out £9019 in railway stock; X gained 50 p. c., Y lost 75 p. c., Z gained 96 p. c.: what sum had each then got?

53. In a school of 1000 children, 24 p. c. are presented for examination in grammar, and of these 26.6 p. c. fail; how many children passed?

54. I bought 15 dozen of wine, 2 of it at 29s. a dozen, ‘6 of it at 375. a dozen, and the remainder at 40s., a dozen; how much more per cent. had I to pay than if I had been charged 33s. 4d. a dozen all round?

55. The standard height for enlistment being 5 feet 5 inches, out of 1950 recruits 748 were under 5 feet 6 inches, 500 between 5 feet 6 inches and 5 feet 7 inches, 429 between 5 feet 7 inches and 5 feet 10 inches, 273 were 5 feet 10 inches and upwards. What percentage of the recruits would have been rejected if the standard had been raised to 5 feet 7 inches, and what p. c. if to 5 feet 10 inches?

56. If a railway 11 miles long ascends 1.25 feet p. c. for 63 of its length, and descends 175 feet p. c. for the remainder, what is the difference of elevation between starting-point and terminus?

57. A, B, and C having a joint capital of £10,000, buy with 93 of it a ship and her cargo, the latter being worth of the former. The ship is lost, the cargo saved; what amount per cent. on his whole capital does each partner lose?

58. A flask contains of brandy and water; the owner drinks half of its contents, and then fills up the flask with water; he then drinks half again, and again fills up with water. What is the percentage of the brandy, and what is that of the water, after each dilution?

59. A contractor undertakes a job which will cost him £9000 to execute, but for which he is to be paid £10,986, subject to a forfeiture of 50 guineas for each day's delay beyond the term fixed for its completion; what percentage of his profits will a delay of 13 days cost him?

60. If, when 25 per cent. is lost in grinding wheat, a

country has to import ten million quarters, but can maintain itself on its own produce if only 5 per cent. be lost, find the quantity of wheat grown in the country.

61. A man bought a Swiss watch bearing a duty of 25 per cent., and sold it at a loss of 5 per cent. Had he sold it for £3 more, he would then have cleared 1 per cent. of the bargain. What was the Swiss watchmaker's price?

62. Certain goods were sold at £126, realizing a profit of 22 92682 per cent. ; what was their prime cost?

63. If the increase in the number of male and female convicts be 18 per cent., while the decrease in the number of males alone is 46 per cent., and the increase in the number of females is 9.8 per cent., compare the number of male and female convicts respectively?

64. There are in a school 52 boys, 38 girls, and 58 infants; what is the percentage of each? If the infants were separated eff, what would be the percentage of girls in the school?

65. A school consists of 97 boys, 108 girls, and 145 infants; how many children are assembled on a day when there are only 18 p. c. absent?

66. If, in composition, the letter e occurs 8.5 per cent. of all the alphabet put together, how many of that letter will be required to print a book containing 500 pages, each page with 30 lines, averaging 11 words of 4 letters in each line ?

67. A school has 500 children on the books, but the average attendance is 23 per cent. below that number; how many children are present when the attendance is only 94 per cent. of the average?

68. If gold be worth £3, 17s. 6d. per oz., and silver be worth 45. 2d. per oz., what percentage in value of gold, and what of silver, will go to make up a statuette consisting of 10 parts silver and one part gold?

69. There sailed in an emigrant ship 280 men, of that number of women, and half as many children as men and women reckoned together; what percentage of men, of women. and of children were on board?

70. There are 3 schools-one of 500 children, another of 600 children, and a third of 900 children. Of the first, 12

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