Average MCQs

The average of 6 observations is 45.5. If one new observation is added to the previous observations, then the new average becomes 47. The new observation is :

The average pocket money of 3 friend A, B, C is Rs. 80 in a particular month. If B spends double and C spends triple of what A spends during that month and if the average of their unspent pocket money is Rs. 60, then A spends (in Rs.)-

The average age of group of 20 girls is 15 years and that of another group of 25 boys it is 24 years. The average age of the two groups mixed together is :

The average of nine number is 50. The average of first five numbers is 54 and that of the last three numbers is 52. Then the sixth number is :

From a class of 42 boys, a boy aged 10 years goes away and in his place, a new boy is admitted. If on account of this change, the average age of the boys in that class increases by 2 months, the age of the newcomer is :

A scored 73, 76, 20 and 7 runs in four out of five innings. What should be his score in fifth innings. If he has to make an average of 55 run in five innings.

Sonali applied for a job of Science teacher in a school. In the test for job, she scored 8 in Physics, 8 in Chemistry, 6 in Biology, and 6.5 in the interview. For calculating the final score, weightage of 2, 3, 3 and 4 were assigned to Physics, Chemistry, Biology and interview, respectively. What is the weighted average score of Sonali?

The average weight of A, B and C is 65 kg. If the average weight of C and B is 61.5 kg, and the average weight of A and C is 68.5 kg, then the weight of C (in kg) is:

The average of 5 consecutive odd numbers is 27. What is the product of the first and the last number?