the bus on a regular schedule ... 3 1/4 hours = 13/4 hours
the express bus ... 2 1/2 hours = 5/2 hours
If you want to know how much travel time you can save by taking the express bus, you can calculate this using the following step:
3 1/4 - 2 1/2 = 13/4 - 5/2 = 13/4 - 10/4 = 3/4 hour
Result: You can save 3/4 hour of your travel time if you choose the express bus.