Mathematics · 2026
JEE Main · 24 January 2026, Shift 2 · Q9
Let X ={x ∈ N: 1 ≤ x ≤ 19} and for some a, b ∈ R, Y ={a x+b: x ∈ X }. If the mean and variance of the elements of Y are 30 and 750, respectively,…
Let $\displaystyle \mathrm{X}=\{x \in \mathrm{~N}: 1 \leq x \leq 19\}$ and for some $\displaystyle a, b \in \mathbb{R}, \mathrm{Y}=\{a x+b: x \in \mathrm{X}\}$. If the mean and variance of the elements of Y are $\displaystyle 30$ and $\displaystyle 750$ , respectively, then the sum of all possible values of $\displaystyle b$ is
Official answer
From NTA’s final answer key for this paper.
(2)
$\displaystyle 60$
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JEE Main 2026 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.