The average of 6 numbers is 7. The average of three numbers of them is 5. What will be the average of remaining numbers?

Answer: Option C

Average of 6 numbers = 7
Sum of 6 numbers = 6 × 7 = 42
Average of three numbers = 5
Sum of three numbers = 5 × 3 = 15
∴ Sum of the remaining three numbers
= 42 - 15 = 27
∴ Required average
= $$\frac{27}{3}$$
= 9