The average of 6 numbers is when one number is discarded the average of the remaining numbers becomes What is the number?

The average of 6 numbers is when one number is discarded the average of the remaining numbers becomes What is the number?

A 7.8

B 9.8

C 10

D 15

Solution

Correct Answer: Option D

8.5 * 6 = 51

7.2 * 5 = 36

The omitted number is (51 - 36) = 15