distance = speed * time, so
2(30-10) = t(30+10)
t = 1
A river flows from north to south at a speed of 10 km/h relative to the bank. A motorboat has a speed of 30
km/h in still water. A fisherman motors north for 2 h, and then, motors south back to his starting point. How
long did the return trip take?
1 answer