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The mean and the variance 10 observations are given to be 4 and 2 respectively. If every observation is multiplied by 2 , the mean and the variance of the new series will be respectively
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Verified Answer
The correct answer is:
8 and 8
$\quad$ Mean $(\bar{X})=4$
Variance $(\mathrm{X})=2$
Number of observations $=10$
New average $=\frac{(4 \times 10) \times 2}{10}=8$
New variance $=(2)^{2} \times$ Variance $(\mathrm{X})$ $=4 \times 2=8$
Option (c) is correct.
Variance $(\mathrm{X})=2$
Number of observations $=10$
New average $=\frac{(4 \times 10) \times 2}{10}=8$
New variance $=(2)^{2} \times$ Variance $(\mathrm{X})$ $=4 \times 2=8$
Option (c) is correct.
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