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AP EAMCET2011MathematicsProbability

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

Options

  1. A1
  2. B2
  3. C3
  4. D4

Correct answer

A. 1

Step-by-step solution

aligned & Mean, m= _ i=1 ^4 p_i x_i & =0 1 10 + 1 2 10 + 2 3 10 + 3 4 10 & =0+ 2 10 + 6 10 + 12 10 & = 20 10 =2 & Variance = _ i=1 ^4 p_i (x_i-m )^2 aligned aligned & = 1 10 (0-2)^2+ 2 10 (1-2)^2+ 3 10 (2-2)^2 & + 4 10 (3-2)^2 & = 4 10 + 2 10 +0+ 4 10 & = 10 10 =1 aligned

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