Two boat landings are 3.0 km apart on the same bank of a stream that flows at 1.6 km/h. A motorboat makes the round trip between the two landings in 50 minutes. What is the speed of the boat relative to the water?

Question

How do I factor in the fact that velocity is subtracted by 1.6 when I wasn't given velocity. );

Answer 1

50 min = .833 hr

t1 = 3/(1.6+v)
t2 = 3/(1.6-v)

.833 hr = t1 + t2