Variance of data 2, 4, 6, 8, 10 is

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13.Statistics

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The variance of the data $2, 4, 6, 8, 10$ is

A

$6$

B

$7$

C

$8$

D

None of these

Solution

(c) Here, $\bar x = \frac{{2 + 4 + 6 + 8 + 10}}{5} = 6$

Hence, variance = $\frac{1}{n}\Sigma {({x_i} – \overline x )^2}$

$ = \frac{1}{5}\{ {(2 – 6)^2} + {(4 – 6)^2} + {(6 – 6)^2} + {(8 – 6)^2} + {(10 – 6)^2}\} $

$ = \frac{1}{5}\left\{ {(16 + 4 + 0 + 4 + 16} \right\}$$ = \frac{1}{5}\left\{ {40} \right\}$ $ = 8$.

Standard 11

Mathematics

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