The average of 41 numbers is 62. The average of the first 18 numbers is 65.5, and the average of the last 24 numbers is 61.5. If the 18th number from the beginning is excluded, then what is the average of the remaining numbers?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 60.725.
Sum of 41 numbers = 41 × 62 = 2542
Sum of first 18 numbers = 18 × 65.5 = 1179
Sum of last 24 numbers = 24 × 61.5 = 1476
18th number = 1179 + 1476 - 2542 = 113
Average of remaining 40 numbers = (2542 - 113) / 40
⇒ 2429 / 40
⇒ 60.725