distance = 30 mph * time
distance = 4 mph * time
distance = 30 mph * t
distance = 4 mph * (17-t)
Since distance is equal then
30 mph * t = 4 mph * (17-t)
30t = -4t + 68
34t = 68
t = 2 hours
We see the return trip time is (17 -t ) which is 15 hours.
The beginning trip time is 2 hours.
Double Check
Beginning trip = 30 miles * 2 = 60 miles
Return trip = 4 miles * 15 = 60 miles.
