Mathematics · 2017
JEE Main · 8 April 2017, Shift 1 · Q85
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 now the…
The mean age of $\displaystyle 25$ teachers in a school is $\displaystyle 40$ years. A teacher retires at the age of $\displaystyle 60$ years and a new teacher is appointed in his place. If now the mean age of the teachers in this school is $\displaystyle 39$ years, then the age (in years) of the newly appointed teacher is :
Official answer
(3)
$\displaystyle 35$
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JEE Main 2017 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.