Mathematics · 2026
JEE Main · 2 April 2026, Shift 2 · Q9
The mean and variance of n observations are 8 and 16, respectively. If the sum of the first ( n-1 ) observations is 48 and the sum of squares of the…
The mean and variance of $\displaystyle n$ observations are $\displaystyle 8$ and $\displaystyle 16$, respectively. If the sum of the first ( $\displaystyle n-1$ ) observations is $\displaystyle 48$ and the sum of squares of the first (n-$\displaystyle 1$) observations is $\displaystyle 496$, then the value of n is :
Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle 7$
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JEE Main 2026 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.