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The mean and variance of a random variable X having binomial distribution are 4 and 2 respectively, then P ( X =1) is

Options

  1. A1 4
  2. B1 32
  3. C1 16
  4. D1 8

Correct answer

B. 1 32

Step-by-step solution

. array c np =4 npq =2 array q = 1 2 p = 1 2 , n =8 p ( X =1)= ^8 C ₁ ( 1 2 ) ( 1 2 )^7=8 1 2^8 = 1 2^5 = 1 32

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