Mathematics · 2026
JEE Main · 24 January 2026, Shift 1 · Q8
The mean and variance of a data of 10 observations are 10 and 2, respectively. If an observations α in this data is replaced by β, then the mean and…
The mean and variance of a data of $\displaystyle 10$ observations are $\displaystyle 10$ and $\displaystyle 2$ , respectively. If an observations $\displaystyle \alpha$ in this data is replaced by $\displaystyle \beta$, then the mean and variance become $\displaystyle 10.1$ and $\displaystyle 1.99$, respectively. Then $\displaystyle \alpha+\beta$ equals
Official answer
From NTA’s final answer key for this paper.
(1)
$\displaystyle 20$
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JEE Main 2026 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.