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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.
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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