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NTA Abhyas 2020
Exam
NTA Abhyas
Year
2020
Subject
Mathematics
Chapter
Statistics

NTA Abhyas 2020 · Mathematics · Statistics

If the mean of 10 observations is 50 and the sum of the squares of...

If the mean of 1010 observations is 5050 and the sum of the squares of the deviations of observations from the mean is 250250, then the coefficient of variation of those observations is

Options

  1. A2525
  2. B5050
  3. C1010
  4. D55

Correct answer

C. 1010

Step-by-step solution

Given, x−=50\overset{-}{x} = 50

∑(xi−x−)2=250[σ2=110×250=25]∑ { \left({x}_{i} - \overset{-}{x}\right)}^{2} = 250 \left[{\sigma}^{2} = \dfrac{1}{10} \times250 = 25\right]

C.V=S.Dx−×100=550×100=10.C. V = \dfrac{S. D}{\overset{-}{x}} \times100 = \dfrac{5}{50} \times100 = 10.
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