COMEDK · Maths · 36. Probability
A coin is tossed until a head appears or until the coin has been tossed three times. Given that 'head' does not appear on the first toss, what is the probability that the coin is tossed thrice?
- A \(\dfrac{1}{8}\)
- B \(\dfrac{1}{4}\)
- C \(\dfrac{3}{8}\)
- D \(\dfrac{1}{2}\)
Answer & Solution
Correct Answer
(D) \(\dfrac{1}{2}\)
Step-by-step Solution
Detailed explanation
Let \(H\) denote head and \(T\) denote tail. The sample space for the experiment is \(S = \{H, TH, TTH, TTT\}\). The condition given is that head does not appear on the first toss. This means the first toss is \(T\). The subset of the sample space where the first toss is \(T\)…
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