# How do you find the speed of the rowboat in still water if it took 3 hours to row a boat 18 km against the current and the return trip with the current took 1 1/2 hours?

##### 2 Answers

Mar 25, 2015

Lets call the speeds

Then the speed out

Return trip speed

If we add these two equations, the

**answer**

It is easy to see that

Mar 25, 2015

Average speed = 8km/hr

Total distance = 18 x 2 = 36km

Total time = 3 + 1.5 = 4.5 hr

Average speed = dist/time = 36/4.5 = 8km/hr