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MHT CET202019 Oct 2020Morning ShiftMathematicsProbabilityActual

Given X B(n, p) , If E(X)=4 and Var (X)=2 4 , then n =

Options

  1. A20
  2. B15
  3. C5
  4. D10

Correct answer

D. 10

Step-by-step solution

(A) array l E ( X )=4 np =4 Var ( X )= npq =2.4 4 q =2.4 q = 3 5 p = 2 5 and n ( 2 5 )=4 n =10 array

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