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The algebraic sum of the deviations of 20 observations measured from 30 is 2 . What would be the mean of the observations?

Options

  1. A30
  2. B32
  3. C30.2
  4. D30.1

Correct answer

D. 30.1

Step-by-step solution

Standard deviation =30 algebraic sum with deviation = x i-h=2 aligned & Mean = x i-h 20 +h= 2 20 +30 & =30+0.1=30.1 . aligned

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