Exercise 28 Page 198

We are told that a student spends $2$ hours watching television and has a grade point average of $2.4.$ We want to know how the data from this student affects the correlation from the previous exercise.

Plot

To determine how this new data point will affect the correlation, let's plot the original data and line of best fit. Then we can add the new data point and see how it relates to the others. Remember that the $x\text{-}$axis represented the number of hours a student spent watching television and the $y\text{-}$axis represented their grade point average.

Is Our Friend Correct?

We want to know if our friend, who said that the new point will weaken the correlation, is correct. Looking at the graph, we can see that this point is relatively far away from the other data points as well as the line of best fit. Including this point would definitely weaken the correlation.