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AP EAMCET202527 May 2025Morning ShiftMathematicsProbabilityActual

Let X be the random variable taking values 1,2, , n for a fixed positive integer n. If P ( X = k )= 1 n for 1 k n , then the variance of X is

Options

  1. An ^2-1 12
  2. Bn ^2+1 12
  3. Cn ^2-1 6
  4. D( n +1)( n +2) 6

Correct answer

A. n ^2-1 12

Step-by-step solution

No Solution

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