Reid and his brother are going to a hockey game on Saturday. The game starts at 4:00 P.M. It takes 15 minutes to drive to the hockey rink, and they want to get there 30 minutes before the game starts to get good seats. What is the latest time Reid and his friends can leave for the game?
15+30 = 45 minutes lead time
so when is 45 minutes before 4:00 ?