A bag contains 19 unbiased coins and one coin... | Probability | JEE Main

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JEE MAIN_2025

070425_S2

Question

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 the drawn coin was unbiased, is $\frac{m}{n}, \operatorname{gcd}(m, n)=1$. then $n^2-m^2$ is equal to:

Select the correct option:

A

72

B

64

C

60

D

80

✓ Correct! Well done.

✗ Incorrect. Try again or view the solution.

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