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The sum of deviations of n number of observations measured from 2.5 is 50 . The sum of deviations of the same set of observations measured from 3.5 is -50 . What is the value of n ?

Options

  1. A50
  2. B60
  3. C80
  4. D100

Correct answer

D. 100

Step-by-step solution

Number of data set =n . Mean =2.5 Sum of deviations =50 Again, sum of deviations, when mean =3.5 is -50 . So, (3.5-2.5) n=50-(-50) n=100

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