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MHT CET202122 Sep 2021Morning ShiftMathematicsStatisticsActual

A random variable X B(n, p) , if values of mean and variance of X are 18,12 respectively, then n =

Options

  1. A54
  2. B18
  3. C12
  4. D55

Correct answer

A. 54

Step-by-step solution

We have n p=18 and n p q=12 aligned & q = 12 18 = 2 3 p =1- 2 3 = 1 3 & n ( 1 3 )=18 n =54 aligned

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