11. Although delays at major airports are now less frequent, it helps to know which airports are likely to throw off your schedule. In addition, if your plane is late arriving at a particular airport where you must make a connection, how likely is it that the departure will be late and thus increase your chances of making the connection? The following data show the percentage of late arrivals and departures during August for 13 airports (Business 2.0, February 2002).

a. Develop a scatter diagram for these data with the percentage of late arrivals as the independent variable.

b. What does the scatter diagram developed in part

(a) indicate about the relationship between late arrivals and late departures?

c. Use the least squares method to develop the estimated regression equation.

d. Provide an interpretation for the slope of the estimated regression equation.

e. Suppose the percentage of late arrivals at the Philadelphia airport for August was 22%.
What is an estimate of the percentage of late departures?