The average of 9 numbers is 56. When one number is removed, the average becomes 54. What number was removed?

Correct option is B

Given :

Average of 9 numbers = 56
Average after removing one number = 54
Number of remaining numbers = 8

Formula Used :
​$$\text{Sum} = \text{Average} \times \text{Number of terms}$$​​

Solution :

Sum of 9 numbers:
9$$\times 56$$​ = 504

Sum of remaining 8 numbers:
8$$\times 5$$​4 = 432

Number removed:
504 - 432 = 72