Brain Teasers
Perfectly Square Island
There is a perfectly square island, with a very deep moat around it, which is 2m wide all the way around. A man needs to get onto this island and has the use of two planks of wood, 2m wide. They are not long enough to bridge the gap (he obviously needs some overlap each side); he has no means to attach the planks together by nails, glue, screws, etc, or to saw them or change them in any other way. He can't jump, swim, fly or get to the island by any other means than by walking over the planks. How can he do it?
Hint
TTTThink about the cornersAnswer
You have two squares, really, an outer and inner one. He can place one plank at an angle of 45 degrees over an outer corner (like a triangle, with a right angle at the corner of the outside square). He can place the other plank from the middle of the first plank to the corner of the island!Hide Hint Show Hint Hide Answer Show Answer
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Comments
exellent i figured he'd pole vault over
but you solusion is much better. well
though out.
but you solusion is much better. well
though out.
I heard the teaser before.
It's not really much of an island, is it? Where's the water?
The water is at the bottom of the very deep hole. Duh.
yes but why have a square island?
The point of a square island is that you can't bridge it with the two planks along a side, but you are able to do it at a corner. Is it not obvious? If it were circular then it won't work......
Good teaser, I figured it out, makes perfect sense!
THAT I 1 OF THE BEST I HAVE HEARD 2DAY!
This is nice.. Took me a while to understand the solution..
A drawing would be good i think..
|---------\/|
| /\|
| -------/ \
| | /| |\ is it clearer
| | | | that way ?
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A drawing would be good i think..
|---------\/|
| /\|
| -------/ \
| | /| |\ is it clearer
| | | | that way ?
| | | |
| -------- |
|------------
damn, i had made such a nice square with two planks and this dumb comment forum destroyed my work of art !
Ok took me awhile to understand the solution too... basically what you are saying is you cut the corner with one plank (both ends on the ground, but then the middle would be over the moat) and then lay the second plank down into the island. That way you are making the distance to the island shorter. Whew
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