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NTA Abhyas JEE Main2020MathematicsStatisticsPractice

If the mean of 10 observations is 50 and the sum of the squares of the deviations of observations from the mean is 250 , then the coefficient of variation of those observations is

Options

  1. A25
  2. B50
  3. C10
  4. D5

Correct answer

C. 10

Step-by-step solution

Given, x - = 50 ∑ x i - x - 2 = 250 σ 2 = 1 10 × 250 = 25 C . V = S . D x - × 100 = 5 50 × 100 = 10 .

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