Chapter 4, Problem 50SE

Semesters and Units The table shows the self-reported number of semesters completed and the number of units completed for 15 students at a community college. All units were counted, but

attending summer school was not included.

a. Make a scatterplot with the number of semesters on the $x\text{-axis}$ and the number of units on the $y\text{-axis}.$ Does one point stand out as unusual? Explain why it is unusual. (At most colleges, full time students take between 12 and 18 units per semester.)

Finish each part two ways, with and without the unusual point,

and comment on the differences.

b. Find the numerical values for the correlation between semesters and units.

c. Find the two equations for the two regression lines.

d. Insert the lines. Use technology if possible.

e. Report the slopes and intercepts of the regression lines and explain what they show. If the intercepts are not appropriate to report, explain why.