The average of 8 numbers is 18. If one of the numbers is excluded, the average becomes 20. Find the excluded number.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. 4.
Given that,
The average of 8 numbers is 18
If one of the numbers is excluded, the average becomes 20
According to the question,
The excluded number = 18 × 8 - 20 × 7 = 144 - 140 = 4