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MHT CET20242 May 2024Morning ShiftMathematicsStatisticsActual

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

Options

  1. A252500
  2. B250500
  3. C250000
  4. D255000

Correct answer

A. 252500

Step-by-step solution

aligned & x =50, Standard deviation =5 & n =100 & Mean x =50 & x_ i 100 =50 & x_ i =5000 & Now, standard deviation = x_i^2 n - ( x_ i n )^2 & 5= x_ i ^2 100 - ( 5000 100 )^2 & 25= x_i^2 100 -(50)^2 & x_i^2 100 =25+2500 & x_i^2=252500 aligned

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