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13.Statistics
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The variance of $10$ observations is $16$. If each observation is doubled, then standard deviation of new data will be -
A
$16$
B
$32$
C
$8$
D
$4$
Solution
$\operatorname{Var}\left(a x_{i}+b\right)=a^{2} \operatorname{var}\left(x_{i}\right)$
Variance on doubling each observation
$=2^{2} \times 16=64$
Std. deviation $=\sqrt{\operatorname{var}}=8$
Standard 11
Mathematics
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