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AP EAMCET202318 May 2023Evening ShiftMathematicsProbabilityActual

If a cubical die is thrown, then the mean and variance of the random variable X , giving the number on the face that shows up, are respectively

Options

  1. A2 7 , 12 35
  2. B7 2 , 12 35
  3. C1 7 , 1 12
  4. D7 2 , 35 12

Correct answer

D. 7 2 , 35 12

Step-by-step solution

aligned & X= 1,2,3,4,5,6 and P(1)=P(2) P(6)= 1 6 & Mean = x_i P= 1+2+3+4+5+6 6 = 21 6 = 7 2 & Variance = x_i^2 P-( Mean )^2 & = 1 6 [1^2+2^2+3^2+4^2+5^2+6^2 ]- 49 4 & = 1 6 91- 49 4 = 35 12 & Variance = 35 12 aligned

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