Question

The mean of five numbers is $27$.If one number is excluded their mean is $25$. find the excluded number.

Answer 1

The mean of $5$ numbers $=27$
Since, Mean$=\frac{\text{sum of given values}}{\text{total number of given values}}$
Hence, sum of numbers $=5\times 27=135$
Given one number is excluded.
So mean of $4$ numbers $=25$
Sum of $4$ numbers $=4\times 25=100$
Therefore, the excluded number $=135–100=35$