WBJEE · Maths · Probability
A biased coin with probability \(p(0 \lt p \lt 1)\) of getting head is tossed until a head appears for the first time. If the probability that the number of tosses required is even is \(\frac{2}{5}\), then \(p=\)
- A \(\frac{1}{4}\)
- B \(\frac{1}{3}\)
- C \(\frac{2}{3}\)
- D \(\frac{3}{4}\)
Answer & Solution
Correct Answer
(B) \(\frac{1}{3}\)
Step-by-step Solution
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