Mathematics · 2025
JEE Main · 7 April 2025, Shift 2 · Q10
A bag contains 19 unbiased coins and one coin with head on both sides. One coin drawn at random is tossed and head turns up. If the probability that…
A bag contains $\displaystyle 19$ unbiased coins and one coin with head on both sides. One coin drawn at random is tossed and head turns up. If the probability that the drawn coin was unbiased, is $\displaystyle \frac{\mathrm{m}}{\mathrm{n}}, \operatorname{gcd}(\mathrm{m}, \mathrm{n})=1$, then $\displaystyle \mathrm{n}^2-\mathrm{m}^2$ is equal to :
Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle 80$
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.