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MHT CET20228 Aug 2022Morning ShiftMathematicsProbabilityActual

For the following frequency distribution The variance is

Options

  1. A2.85
  2. B2.18
  3. C2.37
  4. D2.49

Correct answer

A. 2.85

Step-by-step solution

array cccc x _ i & f _ i & f _ i x _ i & f _ i x _ i ^2 5 & 3 & 15 & 75 6 & 7 & 42 & 252 7 & 4 & 28 & 196 8 & 2 & 16 & 128 10 & 4 N=20 & 40 f_i x_i=141 & 400 f_i x_i^2=1051 array aligned & Variance = f_i x_i^2 N - ( f_i x_i N )^2 & = 1051 20 - ( 141 20 )^2 & =52.55-(7.05)^2 & =52.55-49.7025 & =2.85 aligned

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