Mathematics · 2023
JEE Main · 6 April 2023, Shift 1 · Q17
The mean and variance of a set of 15 numbers are 12 and 14 respectively. The mean and variance of another set of 15 numbers are 14 and σ^2…
The mean and variance of a set of $\displaystyle 15$ numbers are $\displaystyle 12$ and $\displaystyle 14$ respectively. The mean and variance of another set of $\displaystyle 15$ numbers are $\displaystyle 14$ and $\displaystyle \sigma^2$ respectively. If the variance of all the $\displaystyle 30$ numbers in the two sets is $\displaystyle 13$ , then $\displaystyle \sigma^2$ is equal to
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle 10$
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JEE Main 2023 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.