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Sandy Wood
Brain Game: It’s Prison Time!
by Sandy Wood - June 17, 2008 - 6:30 AM

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A prison warden liked to play mind games with his prisoners. One day, he retrieved three of the brightest - Davis, Jones and Smith – and made a deal with them.

“I’m going to line the three of you up in a column alphabetically, facing forward, and then blindfold you. I’ll then place a hat upon each of your heads – I’ve got two yellow ones and three blues one to choose from. Then, I’ll remove the blindfolds. You’re not allowed to move or communicate with one another in any way. I’ll give you ten seconds, and if the first one of you to speak can correctly blurt out what color hat you’re wearing, I’ll pardon all three of you and set you free. But if that first guess is wrong wrong, all three of you will go before the firing squad.”

After a quick huddle, the three readily agreed to the warden’s deal. They spent the night celebrating, and the next day, the three happy prisoners were being processed and released. How did they succeed in outsmarting the warden?

Click here for the answer.

Comments (18)
  1. I’m a little confused. If Smith doesn’t speak up, how does that mean that the other two have different color hats?

    If Smith is silent, it means that at least one of the other two has a blue hat. But it doesn’t mean the other two are different.

  2. Nice one. For those who want to see the more difficult variant, click my name.

  3. The link from the first page that says Click “here” for the answer takes you to the quarter answer from yesterday.

  4. Cool – I got it! Though I guess it was not clear (at least to me) if they could turn around at all, but I guess they don’t need to

  5. at least one of them has to be wearing a blue hat, so if they all answer “blue,” then at least one prisoner will be right.fron

  6. You’re right, C Ster – I’ve corrected the text to indicate that if Smith doesn’t speak up, either Jones or Davis (or perhaps both) are wearing a blue hat.

    Amy, I’ve fixed the link – thanks for the heads up.

    And Gran, if the first guess is wrong, they ALL go before the firing squad. And they sure don’t want that!

  7. They took off the hats to check the color.

  8. I agree with Gran–the text implies that if any of them are right before 10 secs, then they are pardoned, and only if they are all wrong do they get the firing squad. So everyone guessing blue would make at least one of them right.

  9. How can they see the hats in front of them if they are blindfolded before the hats are placed on their heads?

  10. How can they see anything in front of them if they are blindfolded before the hats are placed on their heads?

  11. Lindsay – the text says that the blindfolds are removed after they’re fitted with the hats.

    Amanda – I see what you’re saying; I’ll try a slight rephrase to make it clearer. Thanks!

  12. Thanks Amanda for the backup!

    The rephrase definitely cleared it up Sandy.

  13. I just figured they cheated. They are convicted criminals, after all.

  14. Dang… interesting system of punishment going on at this prison. :D

    Great puzzle!

  15. You’re solution is over-complicated.

    If the guy in the back sees two hats of the same color, he says the opposite color.

    If he says nothing, the second person’s hat must be the other color than the person’s in front of him, so he says that color.

    Two stops – not three.

  16. Or they just cover their mouths.

  17. Sorry PartiallyDeflected, not true. The guy in the back may be stymied if he sees two blue hats, or one of each. If #2 then confidently speaks the opposite of what he sees, he’s still running the risk of being strung up.

  18. In fact, they *are* cheating. The rules clearly state that they are not allowed to communicate in any way. A timed sequence of silence is communication.

    There is no way to solve this without communication.

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