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प्रश्न
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.
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उत्तर
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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