Question

If the variance of the data values in a sample is 121, what is the standard deviation of the data values? A.15 B.12 C.11 D.13

Answer 1

Answer: 11

Step-by-step explanation:

We know that the standard deviation of a data is square root of variance of the data or we can say variance of a data is square of standard deviation of the data.

Given: Variance of data values = 121

Then the standard deviation of the data values will be given by :-

$\sigma=\sqrt{V}\\\\\Rightarrow\sigma=\sqrt{121}\\\\\Rightarrow\sigma=11$

Hence, If the variance of the data values in a sample is 121,  then the standard deviation of the data values will be 11.

Answer 2

Variance is standard deviation squared, so in order to find the standard deviation of 121, you would take the square root:
$\sqrt{121} =11$ (c)