Well....Because I can't see the river and don't know how wide it looks. So.....I would assume the the nearest shore was still referring to starting shore. From the stated problem......couldn't the nearest shore be the starting store?

That along with not realizing 10 min period for both boats......is how I misconstrued.

That's how I did it.

 

Why this so hard from what was said the 10 minute don't matter they both did that they cross 2 times
that means it had to be 3 times then subtract the 400

From what we have been told only can be 2160-400 =1760

Just as WBahn said in post #2

 

Well....Because I can't see the river and don't know how wide it looks. So.....I would assume the the nearest shore was still referring to starting shore. From the stated problem......couldn't the nearest shore be the starting store?

There are TWO starting shores. Each boat started from a different shore. So the very statement, "couldn't the nearest shore be the starting shore," makes no sense. Which shore is the "starting shore"?

The problem states, "they cross at 720 metres from the nearest shore".

When they cross, the point at which they cross is 720 meters from one shore and something MORE than 720 meters from the other shore. The shore that is 720 meters from the point where they cross is the nearer shore because the other shore is further away than 720 meters.

 

Because I am dipolar, not bipolar. I'm always out of kilter.

Please pardon the confusion gentlemen.

 

There are TWO starting shores. Each boat started from a different shore. So the very statement, "couldn't the nearest shore be the starting shore," makes no sense. Which shore is the "starting shore"?

The problem states, "they cross at 720 metres from the nearest shore".

When they cross, the point at which they cross is 720 meters from one shore and something MORE than 720 meters from the other shore. The shore that is 720 meters from the point where they cross is the nearer shore because the other shore is further away than 720 meters.

I found this explanation, clear as mud to me. I think the river has Alligators, I'm not going anywhere near it.

http://gottfriedville.net/mathprob/alg-river.html

kv