The average of 12 numbers is M and the average of 8 of these numbers is P. If the average of the remaining numbers is N then, which of the following options is correct?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e. 3M = 2P + N.
The average of 12 numbers is M
Sum of 12 numbers = 12 × M
The average of 8 of these numbers is P
Sum of 8 of these numbers = 8 × P = 8P
If the average of the remaining numbers is N
Average of the remaining (four numbers) = 4 × N = 4N
Now,
⇒ 12M = 8P + 4N
⇒ 3M = 2P + N