Sum of squares of deviations for 10 observations taken from mean 50 is 250 . co-efficient of variati

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13.Statistics

easy

The sum of squares of deviations for $10$ observations taken from mean $50$ is $250$. The co-efficient of variation is.....$\%$

A

$50$

B

$10$

C

$40$

D

None of these

Solution

(b) ${\rm{S}}{\rm{.D}}{\rm{.}}$

$(\sigma ) = \sqrt {\frac{{250}}{{10}}} = \sqrt {25} = 5$

Hence, coefficient of variation $ = \frac{\sigma }{{{\rm{mean}}}} \times 100$

$ = \frac{5}{{50}} \times 100 = 10\%$.

Standard 11

Mathematics

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