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Posers and Puzzles

Posers and Puzzles

  1. 10 Oct '03 22:13 / 2 edits
    You have for little men...:

    A B C D

    A has a black cap, B has a white cap, C has a white cap and D has a black cap, so there are 2 black and 2 white caps.

    They can not see the colours of their own caps.

    Person A sees nobody.
    Person B sees only A.
    Person C sees only A & B.
    Person D sees nobody.

    They are not allowed to talk to eachother, but if someone knows for sure wich colour is cap has, he must say so.

    This and the other riddle I posted where asked on my Big Math test last week together with 13 other problems of wich most I already forgot!

    Olav

    p.s. I really messed the test up...:'(
  2. 11 Oct '03 09:16
    Originally posted by LivingLegend
    You have for little men...:

    A B C D

    A has a black cap, B has a white cap, C has a white cap and D has a black cap, so there are 2 black and 2 white caps.

    They can not see the colours of their own caps.

    Person A sees nobody.
    Person B sees only A.
    Person C sees only A & B.
    Person D sees nobody.

    They are not allowed to talk to eacho ...[text shortened]... other problems of wich most I already forgot!

    Olav

    p.s. I really messed the test up...:'(
    Ok... What are we supposed to do with our four little men?
  3. 11 Oct '03 09:30
    Originally posted by iamatiger
    Ok... What are we supposed to do with our four little men?
    Hm...I knew I ha forgotten something...

    Can anybody tell wich colour his cap has and prove this!

    Olav

  4. Donation Acolyte
    Now With Added BA
    11 Oct '03 15:51
    Originally posted by LivingLegend
    You have for little men...:

    A B C D

    A has a black cap, B has a white cap, C has a white cap and D has a black cap, so there are 2 black and 2 white caps.

    They can not see the colours of their own caps.

    Person A sees nobody.
    Person B sees only A.
    Person C sees only A & B.
    Person D sees nobody.

    They are not allowed to talk to eacho ...[text shortened]... other problems of wich most I already forgot!

    Olav

    p.s. I really messed the test up...:'(
    I'll assume that the men know how many black and white caps there are, otherwise no-one knows what colour cap he is wearing; also, that they know how the other men are arranged, even if they can't see them.

    C&D do not know what colour caps they are wearing, since if their caps were swapped, it would have no effect on what any of the four men could see. Therefore C doesn't say anything.

    From this, everyone infers that A and B are wearing opposite-coloured hats. Thus C&D know they are also wearing opposite-coloured hats, and B discovers that his hat is white.

    When B says this, A discovers that his hat is black.
  5. 11 Oct '03 19:26 / 2 edits
    Originally posted by Acolyte
    I'll assume that the men know how many black and white caps there are, otherwise no-one knows what colour cap he is wearing; also, that they know how the other men are arranged, even if they can't see them.

    C&D do not know what colour ...[text shortened]... is white.

    When B says this, A discovers that his hat is black.
    You're almost there, but D has nothing to do with this, he can see nothing...

    There are two white caps and two black, and the persons in question know that!

    Their order is 'drawed' in my first post, their line of sight has been told as well there!

    Olav
  6. Donation Acolyte
    Now With Added BA
    12 Oct '03 10:02
    Originally posted by LivingLegend
    You're almost there, but D has nothing to do with this, he can see nothing...

    There are two white caps and two black, and the persons in question know that!

    Their order is 'drawed' in my first post, their line of sight has been told as well there!

    Olav
    I'm confused... what's wrong with my answer?
  7. 12 Oct '03 11:15
    Originally posted by Acolyte
    I'm confused... what's wrong with my answer?
    Well, maybe it is correct, but I think you used the wrong letters, so you confused me too...

    Olav
  8. 12 Oct '03 11:30 / 1 edit
    Originally posted by Acolyte
    I'm confused... what's wrong with my answer?
    After re-reading your post several times, I think I understand what you mean and I think that you are right, I will give you the answer I had in mind:

    B kows the colour of A's cap for he can see him, so if B had the same colour as A, C could know his own colour as there are only two caps of the same colour...C would scream, I know my colour, it is ... ! C does not do this, and so B know that the colour of his cap is different from A's, he knows that the colour of A is for example black, so his cap would be white!

    Olav
  9. 13 Feb '06 04:13
    ok let's assume C is the person in question. If he knows what A & B are whereing and he knows what hes whereing, then he could say that person A has this color, B has this coulor, I have that color, and D has that color.

    or does the person in question know what color he is whereing.
  10. Standard member XanthosNZ
    Cancerous Bus Crash
    13 Feb '06 08:18
    Originally posted by sofar55
    ok let's assume C is the person in question. If he knows what A & B are whereing and he knows what hes whereing, then he could say that person A has this color, B has this coulor, I have that color, and D has that color.

    or does the person in question know what color he is whereing.
    Two years three months thirty days sixteen hours and fourty three minutes.
  11. 14 Feb '06 00:36
    Originally posted by XanthosNZ
    Two years three months thirty days sixteen hours and fourty three minutes.
    what does this have to do with Two years three months thirty days sixteen hours and fourty three minutes
  12. Standard member XanthosNZ
    Cancerous Bus Crash
    14 Feb '06 08:52
    Originally posted by sofar55
    what does this have to do with Two years three months thirty days sixteen hours and fourty three minutes
    It's a puzzle.

    (It's actually the time between your first post in this thread and the one before it)