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MHT CET202020 Oct 2020Evening ShiftMathematicsProbabilityActual

The probability distribution of a random variable X is given by array |c|c|c|c| X =x & 0 & 1 & 2 P ( X =x) & 1 5 & 2 5 & 2 5 array then the variance of X is

Options

  1. A14 25
  2. B9 25
  3. C6 25
  4. D1 25

Correct answer

A. 14 25

Step-by-step solution

array |c|c|c|c| x ₁ & p ( x _ i ) & p _ i x _ i & p _ i x _ i ² 0 & 1 5 & 0 & 0 1 & 2 5 & 2 5 & 2 5 2 & 2 5 & 4 5 & 8 5 array aligned p _ i x _ i &= 6 5 and p _ i x _ i ²= 10 5 =2 Variance &= p _ i x _ i ²- ( p _ i x _ i )² &=2- ( 6 5 )² =2- 36 25 = 14 25 aligned

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