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MHT CET20242 May 2024Evening ShiftMathematicsProbabilityActual

The probability distribution of a random variable X is given by Then the variance of X is

Options

  1. A1.76
  2. B2.45
  3. C3.2
  4. D4.8

Correct answer

A. 1.76

Step-by-step solution

aligned E ( X )= & x_ i P (x_ i ) = & 0(0.4)+1(0.3)+2(0.1)+3(0.1)+4(0.1) = & 1.2 Var ( X ) & = E ( X ^2 )-[ E ( X )]^2 & =0^2(0.4)+1^2(0.3)+2^2(0.1)+3^2(0.1) & +4^2(0.1)-(1.2)^2 & =0.3+0.4+0.9+1.6-1.44 & =1.76 aligned

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