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MHT CET20242 May 2024Evening ShiftMathematicsProbabilityActual

A random variable X has the following probability distribution The mean and variance of X are respectively

Options

  1. A2 3 and 6 1
  2. B2.3 and 0.81
  3. C2.3 and 0.1
  4. D2 3 and 0 9

Correct answer

B. 2.3 and 0.81

Step-by-step solution

aligned Mean & = E ( X )= x_ i P (x_ i ) & =1(0.2)+2(0.4)+3(0.3)+4(0.1) & =2.3 Var ( X ) & = E ( X ^2 )-[ E ( X )]^2 & =1^2(0.2)+2^2(0.4)+3^2(0.3)+4^2(0.1) & =0.2+1.6+2.7+1.6-5.29 & =0.81 aligned

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