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JEE Main20244 Apr 2024Morning ShiftMathematicsStatisticsActual

Let , R . Let the mean and the variance of 6 observations -3,4,7,-6, , be 2 and 23 , respectively. The mean deviation about the mean of these 6 observations is :

Options

  1. A13 3
  2. B16 3
  3. C11 3
  4. D14 3

Correct answer

A. 13 3

Step-by-step solution

aligned & x_i 6 =2 and x_i^2 N - ^2=23 & + =10 & ^2+ ^2=52 aligned solving we get =4, =6 |x_i- x | 6 = 5+2+5+8+2+4 6 = 13 3

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