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MHT CET202120 Sep 2021Morning ShiftMathematicsStatisticsActual

If 1 is added to first 10 natural numbers, then variance of the numbers so obtained is

Options

  1. A8.25
  2. B3.87
  3. C6.5
  4. D2.87

Correct answer

A. 8.25

Step-by-step solution

We have to find variance of numbers 2,3,4, ., 11 . Here x = 2+3+4+ +11 10 = 65 10 =6.5 Variance = ( x _ i - x )^2 n aligned & = [(-4.5)^2+(-3.5)^2+(-2.5)^2+(-1.5)^2+(-0.5)^2+(0.5)^2+(1.5)^2+(2.5)^2+(3.5)^2+(4.5)^2 ] 10 & = 2(20.25+12.25+6.25+2.25+0.25) 10 = 41.25 5 =8.25 aligned

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