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AP EAMCET201822 Apr 2018Evening ShiftMathematicsProbabilityActual

If the probability distribution of a random variable X is given by

Options

  1. A3
  2. B9 4
  3. C3 2
  4. D3 4

Correct answer

D. 3 4

Step-by-step solution

Variance =E (X^2 )-(E(X))^2 aligned & Sum of P (x=x_i )=1 & 1 8 + 3 8 +3 k+k=1 k= 1 8 aligned and the variance aligned =[( & . .0^2 1 8 )+ (1^2 3 8 )+ (2^2 3 8 )+ (3^2 1 8 ) ] & - [ (0 1 8 )+ (1 3 8 )+ (2 3 8 )+ (3 1 8 ) ]^2 = & [ 3 8 + 12 8 + 9 8 ]- [ 3 8 + 6 8 + 3 8 ]^2 = & 24 8 - ( 12 8 )^2=3- ( 3 2 )^2=3- 9 4 = 12-9 4 = 3 4 aligned

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