Q.166- The average age of four boys A, B, C and D is 5 years and the average age A, B, D, E is 6 years. C is 8 years old. The age of E is (in years) :
Q.167- A librarian purchased 50 storybooks for his library. But he saw that he could get 14 books more by spending Rs. 76 more but per book average becomes Rs. 1 less. The average price (in Rs.) of each book he bought, was :
Q.168- A student finds the average of 10, 2 digits numbers. If the digits of one of the numbers interchanged, the average increases by 3.6. The difference between the digits of the 2 digits number is :
Q.169- The mean of 100 observations was calculated as 40. It was founder later on that one of the observation was misread as 83 instead of 53. The correct mean is :
Q.170- Sachin Tendulkar has a certain average for 11 innings. In the 12th innings he scores 120 runs and thereby increases his average by 5 runs. His new average is :