Question

The average of 7 numbers is 8. If a number is added to them, the average becomes 10. What is the number added accordingly?
1. 16
2. 24
3. 32
4. 17

Answer 1

Correct Answer - Option 2 : 24

Given:

The average of 7 number = 8 

The average of 8 number  = 10

Calculation:

The total sum of 7 number = 7 × 8 = 56 

The total sum of 8 number = 8 × 10 = 80

The added number = Total sum of 8 no.-  total sum of 7 no.

⇒ The added number = 80 - 56 = 24

∴ The added number is 24.