The total of 10 number is 462; the average of the first 4 numbers is 52; the average of the last 5 numbers is 38. What is the fifth number?
A
50
B
60
C
64
D
65
Correct Answer: 64
The total of the first 4 numbers = 4×52 = 208 The total of the last 5 numbers = 5×38 = 190 The total of the (4 + 5 = 9) numbers = 208 + 190 = 398 So, the fifth number = 462 - 398 = 64