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If each observation of a dist., whose va...

If each observation of a dist., whose variance is `σ^2` , is multiplied by `lambda`, then the S.D. of the new observations is

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The correct Answer is:
`Rightarrow S . D(lambda x)=|lambda| cdot sigma`

We know, `V ar (aX+b)`=`a^{2}.` `V ar (x)`

Here `b=0, a=\lambda`

$$ \begin{aligned} &\therefore \text { Required variance }=\mathrm{V} \operatorname{ar}(\lambda \mathrm{x})=\lambda^{2} \cdot \mathrm{V} \operatorname{ar}(\mathrm{x})=\lambda^{2} \cdot \sigma^{2} \\ &\Rightarrow \mathrm{S} . \mathrm{D}(\lambda \mathrm{x})=|\lambda| \cdot \sigma ...
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