Attending Class The following data represent the number of days absent, x, and the final grade, y, for a sample of college students in a general education course at a large state university.
(a) Find the least-squares regression line treating number of absences as the explanatory variable and final grade as the response variable.
(b) Interpret the slope and y-intercept, if appropriate.
(c) Predict the final grade for a student who misses five class periods and compute the residual. Is the final grade above or below average for this number of absences?
(d) Draw the least-squares regression line on the scatter diagram of the data.
(e) Would it be reasonable to use the least-squares regression line to predict the final grade for a student who has missed 15 class periods? Why or why not?