Mathematics · 2023
JEE Main · 13 April 2023, Shift 2 · Q29
The mean and standard deviation of the marks of 10 students were found to be 50 and 12 respectively. Later, it was observed that two marks 20 and 25…
The mean and standard deviation of the marks of $\displaystyle 10$ students were found to be $\displaystyle 50$ and $\displaystyle 12$ respectively. Later, it was observed that two marks $\displaystyle 20$ and $\displaystyle 25$ were wrongly read as $\displaystyle 45$ and $\displaystyle 50$ respectively. Then the correct variance is $\displaystyle \_\_\_\_$.
Official answer
From NTA’s final answer key for this paper.
269
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JEE Main 2023 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.