Sarah is a professor of Business Administration at NC State. She lives in Raleigh as shown on the following map. She is trying to make the best choice of how to travel to State College, PA to visit her friend, Kristin, who is a professor of Chemistry at Penn State University. She is considering two choices proposed by her GPS that have red circles around them. (The third option proposed by the GPS is just unacceptable to her as she finds it so boring to drive on that route. As a result, that third option is just out of the question for her.)

As shown on the map, between the two options being assessed by her, the airplane option is faster but more expensive (i.e., requires less time, but causes a higher cost to get to State College, i.e., $496), and the rental car option takes longer in terms of time but costs less (i.e., requires more time, but causes a lower cost, as you will see in your computations later). As you can simply see, there is a trade-off relationship between time and money in the decision she is trying to make. (To simplify matters, we assume both options are the same in terms of other potential criteria such as safety, scenery, and convenience. Then, the problem is simply reduced to a problem of a trade-off relationship between time and money.)