The average of nine numbers is 20. If two of these numbers are removed, then the average becomes 18. What is the sum of the two numbers that are removed?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 54.
We know that,
Average = Sum of observations/Number of observations
The sum of 9 numbers = 9 × 20 = 180
The sum of 7 numbers = 7 × 18 = 126
The sum of the remaining 2 numbers = 180 - 126 = 54