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Perfectly Square Island
Last Post 24 Feb 2012 10:03 AM by jwd217. 2 Replies.
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bal
Basic Member
Basic Member
Posts:147

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23 Feb 2012 11:56 PM
    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?
    johnbaker
    New Member
    New Member
    Posts:3

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    24 Feb 2012 09:58 AM
    The planks, no matter what the width, are longer than 2m corner to opposite corner. Assume they are square , the plank from corner to corner is Sqrt(2^2+2^2)=2.83m so you just need drop it at a 45degree angle from square with one corner on one side and the other will catch on the other side when falling. Not sure if you even need 2.
    jwd217
    New Member
    New Member
    Posts:35

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    24 Feb 2012 10:03 AM
    Place the first plank across the corner of the moat. Then there wiil be about 1.85 meters from the corner of the island to the middle of the plank. So enough overlap so the other plank can be placed there without falling in.
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