Average MCQs

Average age of 20 student is 21 years. 2 students leave the group and 1 new student joins the group. The average now becomes 20 years. If age of one of the student who left the group is 26 years and the one who joined is 20 years, then what is the age (in years) of other student who left the group?

The average of n number is 45. If 60% of the number are increased by 5 each and the remaining numbers are decreased by 10 each, then what is the average of the number so obtained?

Rita buys 5 sarees at an average cost of Rs. 2250. If she buys three more at an average cost of Rs. 2750, what will be the average (in Rs.) of all the sarees she buys?

The average of three consecutive odd numbers is 52 more than $${\frac{1}{3}^{{\text{rd}}}}$$ of the largest of these numbers. What is the smallest of these numbers?

The average of twelve numbers is 39. The average of the last five numbers is 35, and that of the first four numbers is 40. The fifth number is 6 less than the sixth number and 5 more than the seventh number. The average of the sixth and seventh numbers is:

Find the average of the first 20 multiples of 9.

Average temperature of a week is 30°C. If the average of first 4 days was 31°C, then average temperature of the remaining days will be:

The average weight of a certain number of students in a group is 72 kg. If 10 students having an average weight of 78 kg leave and 4 students having an average weight of 80 kg join the group, the average weight of the students in the group decreases by 0.7 kg. The number of students initially in the group is:

The average of prime numbers between 1 and 20 is-