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Cannibals brain teaser

  1. Sep 6, 2005 #1
    There's a boat to cross a river, and it can carry 2 people at once. There are 3 cannibals and 3, well, regular people on one side of the river. They want to get across. If there are more cannibals on one side than regular people, you lose. The boat cannot travel empty.
    Have fun! :biggrin:
  2. jcsd
  3. Sep 6, 2005 #2


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    Two canibals cross.
    One cannibal takes the boat back.
    Two cannibals cross.
    One takes the boat back.
    Two non-cannibals cross.
    A cannibal and a non-cannibal take the boat back.
    Two non-cannibals cross.
    A cannibal takes the boat back.
    Two cannibals cross.
    A cannibal takes the boat back
    Two cannibals cross.
  4. Sep 6, 2005 #3
    sorry, should've mentioned that cannibals cannot pilot the boat
  5. Sep 8, 2005 #4

    Get another boat.

    Can there be a canable on a side when no one else is there or do they start to eat them selves?
  6. Sep 8, 2005 #5
    I must misunderstand the rules somehow..

    C=Canibal c=Non-canibal

    Initially, one C one c must cross. If two or one c cross the remaining will be eaten and zero c isn't an option (no one to use the boat). From there on, the c has to return (if he brought the C that'd be back to square one and nothing else is possible). One c from there would be back to previous state, two c would get the remaining c eaten and one c one C would get the traveling c eaten upon arival at the other side (which would then be two C one c). Unless we're talking some sort of wordplay like the one c staying in the boat with two C on the shore or something to that effect, it's impossible.
  7. Sep 9, 2005 #6
    Your answer is indeed correct. Congratulations. :approve:
  8. Sep 11, 2005 #7
    hi friends, make the cannibal problem a little complicated. suppose, all the regular men can row the boat. and one out of three canibals can row the boat. the story remains same. now try!!

  9. Sep 19, 2005 #8


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    cMMM |.cC
    MMM |.ccC
    CMMM.| cc
    CM |. ccMM
    CcMM.| cM
    cM |. cCMM
    ccMM.| CM
    cc |.CMMM
    ccC.| MMM
    c |. cCMMM
    cC.| cMMM
  10. Sep 19, 2005 #9
    Here is a brain teaser: What do i need to do to start my onw threads??? I can't work it out. PLEASE help.
  11. Sep 21, 2005 #10
    click on the green "new thread" button
  12. Sep 22, 2005 #11
    Cheers, I'm such an idiot for not seeing it...
  13. Oct 20, 2005 #12
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