# The average of 7 numbers is 60. The average of the first three numbers is 50, while the average of the last three is 70. What must be the remaining number ?

The average of 7 numbers is 60. The average of the first three numbers is 50, while the average of the last three is 70. What must be the remaining number ?

A. 75

B. 60

C. 65

D. 55

### **Answer : ** B. 60

## Explanation:

The sum of all the seven numbers = 60 * 7 = 420

The sum of the first three = 50 * 3 = 150

The sum of the last three = 70 * 3 = 210

Remaining Number = 420 - (210 + 150) = 60