When we have the average speed and the distance, we can calculate the travel time as:

Then, we have to add the time of each scale.
a) 97.5 miles at 65mi/h:

b) Lunch break: 45 min = 0.75 h
c) 75 miles at 50 mi/h:

d) Bathroom break: 20 min = 0.33 h
e) 105 miles at 70 mi/h:

Then, we add all the hours for each stage and get:

Answer: the entire trip took 5.58 hours.