A person travels by car from one city to another with different constant speeds between pairs of cities. She drives for 15.0 min at 65.0 km/h, 20.0 min at 75.0 km/h and 60.0 min at 40.0 km/h, and spends 15.0 min eating lunch and buying gas. Determine the average speed for the trip. I know average speed is total distance/total time but I am confused as to how to get the total distance. For the total time I added 15+20+60+15 and got 110 minutes. Would displacement play a part in this problem?