Mathematics · 2024
JEE Main · 30 January 2024, Shift 2 · Q25
Let S_n be the sum to n -terms of an arithmetic progression 3,7,11, … …. If 40<(6/(n(n+1)) Σ_k=1^n S_k)<42, then n equals ____.
Let $\displaystyle S_n$ be the sum to $\displaystyle n$-terms of an arithmetic progression $\displaystyle 3,7,11, \ldots \ldots$.
If $\displaystyle 40<\left(\frac{6}{n(n+1)} \sum_{k=1}^n S_k\right)<42$, then $\displaystyle n$ equals $\displaystyle \_\_\_\_$.
Official answer
From NTA’s final answer key for this paper.
9
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JEE Main 2024 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.