71. A certain factory employed 600 men and 400 women and the average wage was Rs. 25.50 per day. If a woman got Rs. 5 less than a man, then what are their daily wages?
A.Man : Rs.25; Woman : Rs.20
B.Man : Rs.27.50; Woman : Rs.22.50
C.Man : Rs.30; Woman : Rs.25
D.Man : Rs.32.50; Woman : Rs.27.50

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72. The arithmetic mean of: tbe scores of a group of students in a test was 52. The brightest 20% of them secured a mean score of 80 and the dullest 25% a mean score of 31. The mean score of remaining 55% is:
A.45
B.50
C.51.4 approx.
D.54.6 approx.

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73. The average salary of all the workers in a workshop is Rs. 8000. The average salary of 7 technicians is Rs. 12000 and the average salary of the rest is Rs 6000. The total number of workers in the workshop is :
A.20
B.21
C.22
D.23

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74. In a school with 600 students, the average age of the boys is 12 years and that of the girls is 11 years. If the average age of the school is 11 years 9 months, then the number of girls in the school is :
A.150
B.250
C.350
D.450

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75. In an examination, a pupil?s average marks were 63 per paper. If he had obtained 20 more marks for his Geography paper and 2 more marks for his History paper, his average per paper would have been 65. How many papers were there in the examination?
A.8
B.9
C.10
D.11

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76. The average age of students of a class is 15.8 years. The average age of boys in the class is 16.4 years and that of the girls is 15.4 years. The ratio of the number of boys to the number of girls in the class is :
A.1 : 2
B.2 : 3
C.3 : 4
D.3 : 5

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