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Posers and Puzzles

Posers and Puzzles

  1. Standard member Natural Science
    blunderer of pawns
    06 Oct '06 12:38 / 4 edits
    Here's the situation:

    Four men are tied to chairs in this configuration: (the arrows denote which way the men are facing.)

    Man ---) Man ---) Man ---) (Wall) (--- Man

    These are the instructions the men have been given:

    1. Each of you is wearing a hat. Two of you are wearing a blue hat, two of you are wearing a red hat.
    2. In order to save yourselves, one of you must correctly identify the color of your own hat.
    3. You are not allowed to tell anyone else what color their hat is.
    4. You have 10 minutes for one of you to positively identify the color of his own hat. After 10 minutes, or after a wrong guess, a bomb will go off. The bomb will also go off if anyone cheats.

    Because of the manner in which they are tied, none of the men can see what's behind them; they can only see forward. The lone man on the one side of the wall, obviously, cannot see any of the other men. Also, none of the men can take off their hat to identify it. Obviously, any of the 4 of them can take a guess and have a 50% chance of being right. But how can one of them deduce, with 100% certainty, the color of his own hat, given the rules laid out?
  2. 06 Oct '06 12:59
    Originally posted by Natural Science
    Man ---) Man ---) Man ---) (Wall) (--- Man
    call them A,B,C,D from left to right

    either B and C are wearing the same colour, in which case A can tell he is wearing the other colour,

    or B and C are wearing different colours, so A says nothing.
    B then knows C has a different colour to B,
    so B knows what he is wearing the other colour than C is wearing.
  3. 07 Oct '06 15:21
    Originally posted by aging blitzer
    call them A,B,C,D from left to right

    either B and C are wearing the same colour, in which case A can tell he is wearing the other colour,

    or B and C are wearing different colours, so A says nothing.
    B then knows C has a different colour to B,
    so B knows what he is wearing the other colour than C is wearing.
    if B and C are different, they can figure it out, but how does A and D determine what they have?
  4. Subscriber AThousandYoung
    It's about respect
    08 Oct '06 08:14
    Only one person needs to figure it out.
  5. Standard member Natural Science
    blunderer of pawns
    08 Oct '06 12:12
    Againg Blitzer has the correct solution.
  6. 10 Oct '06 20:46 / 2 edits
    The middle person on the left side of the wall can say with 100% certainity. If the first two persons are wearing the same hat then definelty the last person has the answer but if doesnt then the middle one is wearing the opposite color cap from the guy who is sitting in front of him.
  7. 10 Oct '06 21:17
    You can still do this if you add a third hat of one colour (and discard it after shuffling them and 'dealing' them onto people's heads).
  8. 10 Oct '06 22:32
    Well if one man has to identify the colour of their own hat and each man can take their hat off and look at it then surely te rest follows?
    Am i missing something, again.
  9. Standard member XanthosNZ
    Cancerous Bus Crash
    11 Oct '06 01:00
    Originally posted by jimslyp69
    Well if one man has to identify the colour of their own hat and each man can take their hat off and look at it then surely te rest follows?
    Am i missing something, again.
    "Also, none of the men can take off their hat to identify it."
  10. 11 Oct '06 01:01
    That they are tied to the chairs including their arms (and therefore cannot reach up to grab their hats).

    Also, it is important to note that these are the most intelligent people on the planet (all Guttersnipes) and for the purposes of this riddle, they don't tell each other anything - knowing that they are all brainy enough by themselves.
  11. 11 Oct '06 01:04 / 1 edit
    Grrrr....
  12. Standard member CalJust
    It is what it is
    11 Oct '06 10:49
    Originally posted by Gastel
    Grrrr....
    What do you have to edit if you just say Grrrr....???
  13. Subscriber sonhouse
    Fast and Curious
    11 Oct '06 11:58
    Originally posted by CalJust
    What do you have to edit if you just say Grrrr....???
    Figuring out if it's supposed to be Grrr or Grrrr......
  14. Standard member CalJust
    It is what it is
    11 Oct '06 12:08
    Originally posted by sonhouse
    Figuring out if it's supposed to be Grrr or Grrrr......
    In that case, your edit definitely improved it!
  15. 11 Oct '06 21:14
    Originally posted by XanthosNZ
    "Also, none of the men can take off their hat to identify it."
    Not what what it said last time I read it. 4 edits?