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Just Jauntily Jousting (Posted on 2005-08-15) Difficulty: 3 of 5
A Baron, a Count, a Duke and an Earl met at a jousting tournament. In the first round, two met in the first joust, and the other two met in the second joust; the two winners from the first round met at the second round for the final joust. After the jousting, they declared:

  • Baron: I beat the Earl.
  • Count: I faced both the Baron and the Duke.
  • Duke: I didn't make it past the first round.
  • Earl: At the first round, I lost to the Duke.
  • I knew how many were knights, and how many were liars (though not who was what) but that wasn't enough to know what jousts there had been.

    However, I happened to know that a certain joust had taken place (though I didn't know who won and if it had been in the first or the second round) and that allowed me to know every result.

    Can you deduce this?

      Submitted by Old Original Oskar!    
    Rating: 4.0000 (2 votes)
    Solution: (Hide)
    There are 24 possible tournaments -- there are three ways of making the initial pairings, two results for each on of these jousts, and two results for the final joust: 3x2x2x2=24.

    Writing out the 24 combinations show that in 6 of them, there were no knights; in 12, there was just one knight; in 4, two, and in 2, three.

    In all the cases (0, 1, 2 or 3 knights) there are always repeated matches, except in one: when there are 2 knights, there is only one combination with the B-D joust: B beat D, E beat C, and in the final E beat B -- the knights were B and D.

    Comments: ( You must be logged in to post comments.)
      Subject Author Date
    re(3): Ignorance is key - help!owl2005-08-16 13:59:48
    re(2): Ignorance is key - help!Paul2005-08-16 04:31:05
    re: Ignorance is key - help!owl2005-08-16 03:56:09
    SolutionIgnorance is keyPaul2005-08-16 03:15:14
    Hints/TipsWhat he knewFederico Kereki2005-08-15 23:06:38
    Some Thoughtsre: We don't need no stinkin' computers-- FAULTY LOGICe.g.2005-08-15 20:28:47
    SolutionWe don't need no stinkin' computers (except to post comments)Clinton Heath2005-08-15 19:30:15
    SolutionComputer Aided Solutionowl2005-08-15 17:51:37
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