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MHT CET202313 May 2023Morning ShiftMathematicsProbabilityActual

Let X be random variable having Binomial distribution B (7, p ) . If P [ X =3]=5 P [ X =4] , then variance of X is

Options

  1. A7 6
  2. B35 36
  3. C77 36
  4. D1 36

Correct answer

B. 35 36

Step-by-step solution

aligned & P ( X =3)=5 P ( X =4) & ^7 C ₃ p ^3 q ^4=5^7 C ₄ p ^4 q ^3 & 5 p = q & 5 p =1- p & 6 p =1 & p = 1 6 & q =1- 1 6 = 5 6 & Variance = npq & =7 1 6 5 6 & = 35 36 aligned

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