Mathematics · 2025
JEE Main · 7 April 2025, Shift 1 · Q9
The mean and standard deviation of 100 observations are 40 and 5.1, respectively. By mistake one observation is taken as 50 instead of 40. If the…
The mean and standard deviation of $\displaystyle 100$ observations are $\displaystyle 40$ and $\displaystyle 5.1$, respectively. By mistake one observation is taken as $\displaystyle 50$ instead of $\displaystyle 40$ . If the correct mean and the correct standard deviation are $\displaystyle \mu$ and $\displaystyle \sigma$ respectively, then $\displaystyle 10(\mu+\sigma)$ is equal to
Official answer
From NTA’s final answer key for this paper.
(2)
$\displaystyle 449$
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.