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A biased coin with the probability of getting head equal to 1 4 is tossed five times. What is the probability of getting tail in all the first four tosses followed by head?

Options

  1. A81 512
  2. B81 1024
  3. C81 256
  4. D27 1024

Correct answer

B. 81 1024

Step-by-step solution

P( Head )= 1 4 , P( Tail )= 3 4 P(4 Tail and 1 Head )=P(T) P(T) P(T) P(T) P(H)=(P(T))^4 P(H)= ( 3 4 )^4 ( 1 4 )= 81 1024

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