The mean age of 25 teachers in a school is 40yr.

Question

The mean age of 25 teachers in a school is 40yr. A teacher retires at the age of 60yr and a new teacher is appointed in his place. If the mean age of the teachers in this school now is 39yr, then the age (in years) of the newly appointed teacher is .........

Answer: 35

Accepted Answer

$\sum x = 25	imes40=1000$

New sum $=1000-60+x = 39	imes25=975 \implies x=35$

Solutions · 1