WBJEE · Maths · Probability
There are two coins, one unbiased with probaility \(\frac{1}{2}\) or getting heads and the other one is biased with probability \(\frac{3}{4}\) of getting heads. A coin is selected at random and tossed. It shows heads up. Then, the probability that the unbiased coin wa selected is
- A \(\frac{2}{3}\)
- B \(\frac{3}{5}\)
- C \(\frac{1}{2}\)
- D \(\frac{2}{5}\)
Answer & Solution
Correct Answer
(D) \(\frac{2}{5}\)
Step-by-step Solution
Detailed explanation
Let \(E \rightarrow\) Event of head showing up \(E_{1} \rightarrow\) Event of biased coin chosen \(E_{2} \rightarrow\) Event of unbiased coin chosen Now, \(P\left(E_{2}\right)=\frac{1}{2}\) and \(P\left(E_{1}\right)=\frac{1}{2}\) Also,…
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