Exercise 1 Page 715

If a value in a data set is more than $1.5$ times the interquartile range away from the lower or upper quartiles, it is considered an outlier. Therefore, to identify any outliers we first have to find these statistical measures, including any outliers.

Analyzing the Data With Any Outliers

Consider the given data set. Let's organize the information in a list using a graphing calculator. Press $\boxed{\text{STAT}}$ and choose Edit. Enter all of the data into the first list.

Next, analyze the data by pressing the $\boxed{\text{STAT}}$ button again and navigating to the CALC menu. Press $\boxed{\text{ENTER}}$ once to select the $1\text{-Var}$ Stats option and then again to select the list in which we entered the data (usually $\text{L}1).$ This will produce most of the statistical measures we are looking to find.

We can see from our calculator that the mean $\bar{x}$ is $22.8.$ To find the median and quartiles we need to scroll down.