30 miles
first travel = 15 mi
speed = 5 mi/h
Total time
Formula
speed = distance / time
time = distance / speed
time = 30 / 5
time = 6 hours
Total time = 6 hours
-Time to ride 15 miles
time = 15/5
time = 3 hours
Then, after her break, Sandra rode for 3 more hours