Mathematics · 2025
JEE Main · 4 April 2025, Shift 1 · Q9
A box contains 10 pens of which 3 are defective. A sample of 2 pens is drawn at random and let X denote the number of defective pens. Then the…
A box contains $\displaystyle 10$ pens of which $\displaystyle 3$ are defective. A sample of $\displaystyle 2$ pens is drawn at random and let $\displaystyle X$ denote the number of defective pens. Then the variance of $\displaystyle X$ is
Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle \frac{28}{75}$
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.