25. Find the perimeter of the plot; of the lawn; of the garden; of the flower bed; of the walk. Find the area in square yards : 30. How much will it cost to fence the plot at $34 per rod ? 31. How much will it cost to pave the walk at $1.55 per square yard ? 32. How much will it cost to spade the flower bed at 5 cents per square yard ? 33. How much will it cost to sod the lawn, excluding the flower bed, at $0.25 per square yard ? 34. A board 16 ft. long contains 9 sq. ft. Find its width. 35. A room is 20 ft. long, 16 ft. wide, and 10 ft. high. How much will it cost to plaster the walls and ceiling at 20 cents a square yard ? 36. How many gallons of water are there in a tank 12 ft. long, 8 ft. wide, and 6 ft. deep if it is half full ? 37. Find the cost of 40 boards, each 14 ft. long, 18 in. wide, and 1 in. thick, at $ 20 per M. 38. A city 5 miles long and 3 miles wide is equal in area to how many farms of 160 acres each ? 39. How many sods 16 in. square will be required to turf a lawn 106 ft. 8 in. long and 50 ft. wide ? 40. What will be the cost of painting the outside of a house 48 ft. long, 30 ft. wide, and 20 ft. high, with 2 coats of paint, at 18 cents a square yard ? PERCENTAGE Per cent means by the hundred or hundredths. The sign for it is %. We may express the per cent of a number either as a common fraction or a decimal. Thus, 6% = 160 = .06; 6% of 500 means too of 500, which equals 30; or, expressed decimally, .06 of 500 = 30. 2% of a number ineans tấo or .02 of a number. 25% of a number means to or .25 of a number. 1. What term in common fractions corresponds to the number before the sign %? to the sign % ? 2. What expresses the numerator and what indicates the denominator of the fractions represented by the following: 1% ? 20%? 40% ? 90%? 6% ? 30 %? 75% ? 100% ? 3. Find 6% of 100. 16.8% of 75 331 100 Changing per cents to equivalents. Since 5%=.05=160 = 2, these expressions may be called equivalents. 1. Give the fractional and decimal equivalents for 10 %; 6 %; 4%; 20 %; 25 %. 5. Read the following equivalents : 2. 1%, 20%, .20, } ,. 100' 121 3. 121%, .12), 100' 6. 8, 80%,.80, 4 4. 4840%, .40, 4 7. 871, 873%,.871, 5 100 8. Change the fractions }, , , $ to their equivalent decimals and per cents; also š, s, š, z. = 1= 8)1.00 or 121% .20 .121 f = 2 x .20 = .40 or 40% *= 3 x .12} = .37} or 371 % 3 x.20 = .60 or 60 % =5 .121 = .62] or 621 % = 4x .20 = .80 or 80% x = 7 *.121 = .871 or 871% 25. Change to their equivalent decimals and per cents : 21. 10. } 14. à 18. 19. % 12. 1 16. 1 20. } 24. } 22. 26. 11. 15. 23. 27. } 28. 1o Give the products rapidly: 29. 2x.33} 32. 5x.121 30. 5x.163 33. 74.121 31. 3 x.121 34. 3 x.83 35. 4x.12) 38. 4*.011 39. 3x.16 40. 4*.163 Memorize the following table: = 50% = 66%% 1=25% = 75% ž= 20% = 831% =121% B=371% =621% x=871% i=81% = 413% To = 64% 20 = 5% 25 = 4% Name rapidly the fractional equivalents of the following per cents : Write the equivalents of the following in decimals, thus : 1%=.01; 32%=.32; 1%=.002; etc. 61. 1% 67.6% 73. 50% 79. 13% 62. 32% 68. 3% 74. 3% 80. 131% 63. 1% 69. 11% 75. 6% 81. $% 64. 2% 70. 1% 76. 1% 82. 100% 65. 161% 71. 4% 77. 7% 83. 123% 66. 1% 72. 431% 78. 3% 84. 127% Finding a given per cent of a number. Recite the following thus : Look at “ 663%,” think “ ”. 1. 663% of 18. 12. 371% of $ 7200. 2. 331% of 90. 13. 121% of $6400. 3. 50% of $500. 14., 75% of $4800. 4. 25% of $2000. 15. 663% of $999. 5. 75% of 16 inches. 16. 80% of 60 sheep. 6. 20% of 100 yards 17. 60% of 75 horses. 7. 40% of 60 feet. 18. 40% of 90 miles. 8. 60% of 40 miles. 19. 871% of $160. 9. 80% of 75 gallons. 20. 621% of $240. 10. 163% of $6000. 21. 371% of $880. 11. 831% of $1200. 22. 121% of 24. Written Work 1. A man had 100 cows and sold 25% of them. How many did he sell? 25% = .25 100 cows .25 As 25% = .25 we multiply 100 by .25. The 500 result is 25, the number sold. 200 25.00 number sold Find results decimally: 2. 50% of 750 4. 40% of 8.75 6. 32% of 1000 3. 25% of 85.5 5. 28% of 840 7. 75 % of 980 8. John earns $21.60 per month, and spends 75% for clothes. How much do his clothes cost him ? |