Mean age can be calculated as
x−=25x1+x2+…x25=40
⇒ x1+x2+…+x25=1000
Let age of new teacher be A, then
1000−60+A=39×25=975
⇒ A=975−940=35
The mean age of 25 teachers in a school is 40 years. A teacher retires at the age of 60 years and a new teacher is appointed in his place. If the mean age of the teachers in this school now is 39 years, then the age (in years) of the newly appointed teacher is
Held on 8 Apr 2017 · Verified 6 Jul 2026.
35
40
25
30
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