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AP EAMCET202017 Sep 2020Evening ShiftMathematicsStatisticsActual

If the mean of 100 observations is 50 and their standard deviation is 5 , then the sum of squares of all observations is

Options

  1. A50000
  2. B250000
  3. C252500
  4. D255000

Correct answer

C. 252500

Step-by-step solution

Given; ( x =50 ) (n=100 ) and (S . D( )=5 ) As, ( x = x_i n x_i=n . x =5000 ). Also, S.D. is given by, ( aligned & = x_i^2 n - ( x_i n )^2 ^2 & = x_i^2 n -( x )^2 25= x_i^2 100 -(50)^2 x_i^2 & =252500 aligned )

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