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AP EAMCET20226 Jul 2022Morning ShiftMathematicsStatisticsActual

If the total number of observations is 20, x_i=1000 and x_i^2=84000 , then the variance of the distribution is

Options

  1. A1500
  2. B1600
  3. C1700
  4. D1800

Correct answer

C. 1700

Step-by-step solution

Given number of observation is 20 . aligned & x =20, x _ i =1000 and x _ i ^2=84000 & ^2= 1 x _ i =1 ^ x ( x _ i - x )^2 & = 1 x _ i =1 ^ x ( x ₁^2+ x ^2-2 x _ i x ) & ^2= 1 x x _ i ^2- x ^2= 1 x x _ i ^2- ( 1 x x _ i )^2 & ^2= 1 20 84000- ( 1 20 1000 )^2 & ^2=4200-2500=1700 aligned

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