Date: 09-13-08 13:46
Yes, I hope this will be a general chat thread where people can chat and get to know each other. Everyone is welcome!
Yes, the bear was white! Good for you! Thanks for taking the time to think about the puzzle, and for bringing in a friend; puzzles are more fun if you work on them with someone. I have seven more puzzles, ranging from relatively easy to one that has driven people nuts for centuries (although solutions are known), so if anyone wants to try another one sometime, let me know.
I owe you an explanation of why the bear puzzle works. Once you realize that the man started (and ended) at the north pole, the rest follows, since the bear was a polar bear, therefore it was white.
Now consider what happens if the man starts at the north pole:
1. The walk 60 miles south takes him 60 miles from the north pole.
2. The walk 60 miles east takes him along a circle of constant latitude; on this walk he will always be 60 miles from the north pole, with the north pole always on his left.
3. The walk 60 miles north then takes him back to the north pole!
Once you see the above, it's not too hard to believe that the north pole is the only place in the northern hemisphere from which he could have started.
(Actually he could have done the walk from some points near the south pole too, still winding up back where he started, but we don't have to worry about those places since the puzzle said he saw a bear, and there are no bears down there.)
I hope this explanation helps.
The remnants of Hurricane Ike are supposed to roll over my area tomorrow, brnging 3-5 inches of rain. UGH!
"Believe, when you are most unhappy, that there is something for you to do in the world. So long as you can sweeten another's pain, life is not in vain."--Helen Keller