Mathematics · 2021
JEE Main · 31 August 2021, Shift 2 · Q77
The mean and variance of 7 observations are 8 and 16 respetively. If two observations are 6 and 8, then the variance of the remaining 5 observations…
The mean and variance of $\displaystyle 7$ observations are $\displaystyle 8$ and $\displaystyle 16$ respetively. If two observations are $\displaystyle 6$ and $\displaystyle 8$, then the variance of the remaining $\displaystyle 5$ observations is :
Official answer
(2)
$\displaystyle \frac{536}{25}$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.