The mean monthly salary of five employees in a school is `3000. If one of the employees retires, then the mean monthly salary of the remaining employees becomes `3200. What was the monthly salary of the employee who retired at the time of the retirement?

We know that,

Where, = Mean, x_i = observations and n = no. of observations.

Let the salary of the retired employee be x and sum of other employees’ salary be S.

⇒ S + x = 15000……… (1)

Also,

⇒ S = 12800

Substituting value of S in (1), we get -

12800 + x = 15000

⇒ x = 2200

∴ salary of retired employee = 26