Question

5.) A boat makes a trip downstream in 5 hours. The return trip against the current takes 12 hours. If the speed of the current is 3 1/2 km/h, what is the speed of the boat in still water?
6.) How far does the boat referred to in Exercise 5 travel (one-way)?

Answer 1

since distance = speed * time,

(x+3.5)(5) = (x-3.5)(12)
x = 8.5

Now you can easily show how far it went.