SOLUTION: A BOAT TRAVELS 8KM UPSTREAM AND 8KM BACK. TIME FOR THE ROUND TRIP IS 9HRS. THE SPEED OF THE STREAM IS 5KM/HR. WHAT IS THE SPEED OF THE BOAT IN STILL WATER?

Question 321379: A BOAT TRAVELS 8KM UPSTREAM AND 8KM BACK. TIME FOR THE ROUND TRIP IS 9HRS. THE SPEED OF THE STREAM IS 5KM/HR. WHAT IS THE SPEED OF THE BOAT IN STILL WATER?

Answer by galactus(183) (Show Source): You can put this solution on YOUR website!
Let r be the rate of the stream.
Then, upstream the boat travels at a rate of 5-r
Downstream, it travels at a rate of 5+r
Since d=rt, then t=d/r.
The trip takes 9 hours altogether, so we have:

Solving for r gives us km/hr
RELATED QUESTIONS
A Paddleboat can move at the speed of 8km/hr in still water. The boat is paddled 10km... (answered by mananth)

A boat, whose speed in still water is 8Km per hour travels 12Km upstream and then 16Km... (answered by jorel1380)

A boat, whose speed in still water is 8Km per hour travels 12Km upstream and then 16Km... (answered by emargo19)

A boat travels at an average speed 15km/h in still water. The boat travels 12km... (answered by ewatrrr)

A man can row at 6km/h in still water. He rows 8km up a river and then back again, taking (answered by jorel1380)

It took a crew 4h 30m to row 8km upstream and back again. If the rate of flow of the... (answered by jorel555)

A woman rows a boat upstream from one point on a river to another point 8km away in 1... (answered by solver91311)

A man can row 20km downstream in the time he takes to row 8km upstream. He rows... (answered by Paul)

Hi A man can row 8km per hour in still water. If it takes him 3 times as long to row... (answered by ikleyn)