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MHT CET20227 Aug 2022Evening ShiftMathematicsStatisticsActual

The variance of first 10 multiples of 3 is

Options

  1. A74.15
  2. B73.15
  3. C74.25
  4. D70.15

Correct answer

C. 74.25

Step-by-step solution

Variance aligned & = x_i^2 n -( x )^2= 3^2+6^2+9^2+ . .+30^2 10 - ( 3+6+9+ +30 10 )^2 & = 3^2 (1^2+2^2+3^2 .0^2 ) 10 -3^2 ( 1+2+3+ . .+10 10 )^2 & = 9 10 11 21 6 10 -9 ( 10 11 2 10 )^2= 33 21 2 - 9 121 4 & = 99 4 (14-11) & = 99 3 4 =24.75 3=74.25 aligned

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