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Question
If the sum of the squares of deviations for 10 observations taken from their mean is 2.5, then write the value of standard deviation.
Solution
The sum of the squares of deviations for 10 observations, taken from their mean, is 2.5.
Square of each deviation = \[\frac{2 . 5}{10} = 0 . 25\]
Standard deviation = \[\sqrt{0 . 25} = 0 . 5\]
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