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MHT CET202211 Aug 2022Morning ShiftMathematicsStatisticsActual

In an experiment with 15 observations on x , we have x^2=2830, x=170 . One observation that was 20 was found to be wrong and was replaced by the correct value 30 , then the corrected variance is

Options

  1. A177.33
  2. B188.66
  3. C80.33
  4. D78

Correct answer

D. 78

Step-by-step solution

aligned & Correct variance = x^2-20^2+30^2 15 - ( x-20+30 15 )^2 & = 2830-400+90 15 - ( 170-20+30 15 )^2 & =222-144=78 aligned

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