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Another river problem

  1. Aug 26, 2005 #1
    A little harder then the lion/goat/cabbage but easier (IMO) then the King/Queen/Peasant+wifes.

    A mother, a father, two sons, two daughters, a criminal and a cop need to cross a river. They have a boat for two, as usual in these situations.

    1. The mother cannot be in the presense of any sons unless the father is present.
    2. The father cannot be in the presence of any daughters unless the mother is present.
    3. The criminal cannot be in the presence of anyone unless the cop is present.
    4. Only the father, the mother and the cop can operate the boat.
    5. "being in the presence of" includes both sides and the boat.
    6. Any oddball logic mistakes I made in writing this are mistakes, not an indication that this is some kind of word puzzle rather then a logic puzzle.
  2. jcsd
  3. Aug 26, 2005 #2


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    Let's see here:
    Cop and prisoner cross.
    Cop takes the boat back.
    Cop and one daughter cross.
    Cop and prisoner cross back.
    Mother and daughter cross
    Mother takes the boat back.
    Mother and father cross
    Father takes the boat back
    Cop and prisoner cross
    Mother takes the boat back
    Father and mother cross
    Father takes the boat back
    Father and son cross
    Cop and prisoner take the boat back
    Cop and son cross
    Cop takes the boat back
    Cop and prisoner cross
  4. Aug 26, 2005 #3
    Correct. Not that you need me to tell you :-).
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