Mathematics · 2026
JEE Main · 6 April 2026, Shift 1 · Q9
A data consists of 20 observations x_1, x_2, …, x_20. If Σ_i=1^20(x_i+5)^2=2500 and Σ_i=1^20(x_i-5)^2=100, then the ratio of mean to standard…
A data consists of $\displaystyle 20$ observations $\displaystyle x_1, x_2, \ldots, x_{20}$. If $\displaystyle \sum_{i=1}^{20}\left(x_i+5\right)^2=2500$ and $\displaystyle \sum_{i=1}^{20}\left(x_i-5\right)^2=100$, then the ratio of mean to standard deviation of this data is:
Official answer
From NTA’s final answer key for this paper.
(2)
$\displaystyle 3$:$\displaystyle 1$
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JEE Main 2026 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.