Question

1. suppose a data set has a variance of 72.25. what is the standard deviation of this data set?

Explanation:

Step1: Recall the relationship between variance and standard deviation

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

Step2: Substitute the given variance into the formula

We know the variance $\sigma^2 = 72.25$. So we need to calculate $\sqrt{72.25}$.
Since $8.5\times8.5 = 72.25$, so $\sqrt{72.25}=8.5$.

Answer:

8.5