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2 years ago

"if the standard deviation of a group of 20 scores is 15, what is the variance?"

Mathematics

1 answer:

DerKrebs [107]2 years ago

7 0

We have been given that the standard deviation of a group of 20 scores is 15 and we are asked to find variance.

Since we know variance is square of standard deviation. In order to find out the variance of the given data we have to take the square of 15.

$\text{ Variance}=\sigma^{2}\\
=15^{2}=225$

Therefore, our variance is 225.

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