51. A pupil’s marks were wrongly entered as 83 instead of 63. Due to that the average marks for the class got increased by half. The number of pupils in the class is:
a) 10
b) 20
c) 40
d) 73
52. The average age of 15 students of a class is 15 years. Out of these, the average age of 5 students is 14 years and that of the other 9 students is 16 years. The age of the 15th student is:
a) 11years
b) 14 years
c) 15 years
d) 15 2/7 years.
53. The average of 11 numbers is 10.9. If the average of the first six numbers is 10.5 and that of the last six numbers is 11.4 then the middle number is:
a) 11
b) 11.3
c) 11.4
d) 11.5
54. The average weight of three boys A,B and C is 54 1/3 kg, while the average weight of three boys B,D and E is 53 kg. What is the average weight of A, B, C, D and E?
a) 52.4 kg
b) 53.2 kg
c) 53.8 kg
d) Data inadequate
e) None of these
55. The average temperature of the town in the first four days of a month was 58 degrees. The average for the second, third, fourth and fifth days was 60 degrees. If the temperatures of the first and fifth days were in the ratio 7: 8, then what is the temperature on the fifth day?
a) 64 degrees
b) 62 degrees
c) 56 degrees
d) None of these
ANSWERS
