Question

find the standard deviation, (sigma), of the data. 97, 122, 143, 155, 138 (overline{x}=131) variance((sigma^{2}) = 401.2) (sigma=) round to the nearest tenth.

Explanation:

Step1: Recall the formula for standard deviation

The standard deviation $\sigma$ is the square root of the variance $\sigma^{2}$. So, $\sigma=\sqrt{\sigma^{2}}$.

Step2: Substitute the given variance value

Given $\sigma^{2} = 401.2$, then $\sigma=\sqrt{401.2}$.
Using a calculator, $\sqrt{401.2}\approx20.0$.

Answer:

$20.0$