Bob is having a nice camping/fishing trip along a river. He leaves his campsite early in the morning, and gets on his boat, heading full throttle upstream.
After going for exactly one mile, his hat flips off of his head, and starts floating downstream. Bob doesn't realize that his hat has fallen off for five minutes, but then he notices that it's missing, and turns full throttle downstream.
He finally catches the hat at exactly the same spot as he camped that morning. The question is, how fast was the water traveling?
(Assume that he travels the same speed the entire time and that there is no turn around time.)
(In reply to
re(2): General Shortcut Formula by Jayaram S)
Yes thanks, I realise after reading all the comments that everyone has taken into account the relative speed of the boat. I read the question as saying he travels at the same speed regardless if he's going with the current or not:"Assume that he travels the same speed the entire time" . I still say its ambiguous at least (and at worst, poorly worded), but it makes more sense the 'your' way.
re(3): General Shortcut Formula
