Mathematics · 2021
JEE Main · 27 August 2021, Shift 2 · Q90
An online exam is attempted by 50 candidates out of which 20 are boys. The average marks obtained by boys is 12 with a variance 2. The variance of…
An online exam is attempted by $\displaystyle 50$ candidates out of which $\displaystyle 20$ are boys. The average marks obtained by boys is $\displaystyle 12$ with a variance 2. The variance of marks obtained by $\displaystyle 30$ girls is also 2. The average marks of all $\displaystyle 50$ candidates is 15. If $\displaystyle \mu$ is the average marks of girls and $\displaystyle \sigma^2$ is the variance of marks of $\displaystyle 50$ candidates, then $\displaystyle \mu+\sigma^2$ is equal to \_\_\_\_.
Official answer
25
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.