21) The average of 8 numbers is 12. If each number is increased by 2, the new average will be
(a) 12
(b) 14
(c) 13
(d) 15
22) The average of x, y and z is 45. x is as much more than the average as y is less than the average. Find the value of z.
(a) 45
(b) 25
(c) 35
(d) 15
23) The average age of 24 students and the principal is 15 years. When the principal’s age is excluded, the average age decreases by 1 year. What is the age of the principal?
(a) 38
(b) 40
(c) 39
(d) 37
24) The average age of 8 persons in a committee is increased by 2 years when two men aged 35 years and 45 years are substituted by two women. Find the average age of the two women.
(a) 48
(b) 45
(c) 51
(d) 42
25) The average temperature on Monday, Tuesday and Wednesday was 41 °C and on Tuesday, Wednesday and Thursday it was 40 °C. If on Thursday it was exactly 39 °C, then on Monday, the temperature was
(a) 42 °C
(b) 46 °C
(c) 23 °C
(d) 26 °C
26) If we take four numbers, the average of the first three is 16 and that of the last three is 15. If the last number is 18, the first number is
(a) 20
(b) 21
(c) 23
(d) 25
27) The average age of a group of men is increased by 5 years when a person aged 18 years is replaced by a new person of aged 38 years. How many men are there in the group?
(a) 3
(b) 4
(c) 5
(d) 6
28) Find the average of the first 97 natural numbers.
(a) 47
(b) 37
(c) 48
(d) 49
29) The average of ten numbers is 7. If each number is multiplied by 12, then the average of the new set of numbers is
(a) 7
(b) 19
(c) 82
(d) 84
30) With an average speed of 40 km/h, a train reaches its destination in time. If it goes with an average speed of 35 km/h, it is late by 15 minutes. The length of the total journey is –
(a) 40 km
(b) 70 km
(c) 30 km
(d) 80 km
Good Luck!!