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AP EAMCET202124 Aug 2021Evening ShiftMathematicsProbabilityActual

Let X be a random variable with probability distribution function, P(X=x)=K ( 2 5 )^x, x=1,2,3, Then, value of K is

Options

  1. A3 5
  2. B5 3
  3. C3 2
  4. D2 3

Correct answer

C. 3 2

Step-by-step solution

Given, P(X=x)=K(2 / 5)^x We know P_i=1 K [ ( 2 5 )+ ( 2 5 )^2+ ( 2 5 )^3+ ]=1 aligned & K ( 2 5 1-2 / 5 )=1 & K 2 3 =1 K=3 / 2 aligned

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