Mathematics · 2024
JEE Main · 27 January 2024, Shift 1 · Q20
Let a_1, a_2, … a_10 be 10 observations such that Σ_k =1^10 a_k =50 and Σ_∀ k < j a_k. a_j =1100. Then the standard deviation of a_1, a_2, …, a_10 is…
Let $\displaystyle \mathrm{a}_1, \mathrm{a}_2, \ldots \mathrm{a}_{10}$ be $\displaystyle 10$ observations such that $\displaystyle \sum_{\mathrm{k}=1}^{10} \mathrm{a}_{\mathrm{k}}=50$ and $\displaystyle \sum_{\forall \mathrm{k}<\mathrm{j}} \mathrm{a}_{\mathrm{k}} . \mathrm{a}_{\mathrm{j}}=1100$. Then the standard deviation of $\displaystyle \mathrm{a}_1, \mathrm{a}_2, \ldots, \mathrm{a}_{10}$ is equal to:
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle \sqrt{5}$
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JEE Main 2024 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.