Mathematics · 2025
JEE Main · 22 January 2025, Shift 1 · Q9
Two balls are selected at random one by one without replacement from a bag containing 4 white and 6 black balls. If the probability that the first…
Two balls are selected at random one by one without replacement from a bag containing $\displaystyle 4$ white and $\displaystyle 6$ black balls. If the probability that the first selected ball is black, given that the second selected ball is also black, is $\displaystyle \frac{\mathrm{m}}{\mathrm{n}}$, where $\displaystyle \operatorname{gcd}(\mathrm{m}, \mathrm{n})=1$, then $\displaystyle \mathrm{m}+\mathrm{n}$ is equal to :
Official answer
From NTA’s final answer key for this paper.
(1)
$\displaystyle 14$
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.