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MHT CET20226 Aug 2022Morning ShiftMathematicsStatisticsActual

In an experiment with 15 observations the results were available and X^2=2830, X=170 , one observation that was 20 , was found wrong and was replaced by the correct value 30 , then the corrected variance is

Options

  1. A78.00
  2. B188.66
  3. C83.30
  4. D177.33

Correct answer

A. 78.00

Step-by-step solution

aligned & correct x^2=2830-20^2+30^2=3330 & correct x=170-20+30=180 & correct variance = 1 15 x^2- ( 1 15 x )^2 & = 1 15 3330- ( 1 15 180 )^2 & =222-144 & =78 aligned

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