Mathematics · 2024
JEE Main · 6 April 2024, Shift 1 · Q18
The mean and standard deviation of 20 observations are found to be 10 and 2, respectively. On rechecking, it was found that an observation by mistake…
The mean and standard deviation of $\displaystyle 20$ observations are found to be $\displaystyle 10$ and $\displaystyle 2$ , respectively. On rechecking, it was found that an observation by mistake was taken $\displaystyle 8$ instead of $\displaystyle 12$ . The correct standard deviation is
Official answer
From NTA’s final answer key for this paper.
(2)
$\displaystyle \sqrt{3.96}$
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JEE Main 2024 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.