Questions tagged [hat-guessing]
Cooperative games where a team of players must try to guess the color of their hat, but can only see their teammates' hats.
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Guess color of your hat cooperatively, goal is all correct or all incorrect [duplicate]
Let n be an integer. n logicians standing in a circle are blindfolded and a hat of either red or blue is put on each person's head. Blindfolds are then removed; each person can now see the color of ...
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Guess Hat Collor [closed]
Five elders are sitting around a large bonfire. They know that Oluf will put a hat of one of four colours (red, green, blue or yellow) on each elder’s head, and after a short time for silent ...
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Infinitely many deaf dwarves
A beautiful puzzle, and I know the solution. I read it on an Italian riddle forum.
An evil witch kidnaps infinite (countable) dwarves. The witch tells the dwarves that the next day she will put them ...
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Infinitely many dwarves wearing hats of 2 colours
I have heard of the puzzle with 100 or 10 dwarves wearing a hat of a color, either red or blue, and standing in a straight line, and having to guess the color of their own hat - it's quite easy.
The ...
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Cooperative guessing game: no incorrect guesses
There are 15 players who will play a cooperative game. They begin by closing their eyes. A referee will place either a black hat or a white hat (chosen by fair coin flip) on each player's head. The ...
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12 logicians each have a number written on their foreheads
12 logicians each have a number written on their foreheads, visible to all but themself. One day, a meta-logician comes by and remarks, "I see all the numbers are distinct natural numbers." ...
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Sheets of paper on foreheads in a quiz show [duplicate]
I have got a puzzle that I wanted to share.
In a quiz show, three candidates were shown five slips of paper - three white and two black. Then they were blindfolded and one of the slips of paper was ...
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Five Hats and Three Logicians
Three logicians were seated around a table. They were blindfolded and a colored hat was placed on each of their heads. They were told a true statement
The hats on your heads were chosen among 3 ...
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Red and Blue in the Chocolate Fountain Room
Where: Hackanoogie Prison. When: Who cares?
The Master Key Keeper had had a really good day and in a fit of insanity and niceness decided to let all the inmates to go free if they manage to carry ...
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Guess the hat colors - Riddle 1
I have created several riddles with my brother, and one of my favourite ones is this one. It is based on the classic prisoner hat riddle, but it has a twist.
TASK: You have to guess which ones are ...
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Four prisoners wearing black and white hats
There are four prisoners. All four prisoners will be freed, if at least one of them correctly guesses the color of the hat on his head.
They can't speak to each other, and they can't touch each other.
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Again! 6 prisoners, 2 colors, one mute
After that last game, the warden didn't like that they escaped. So he made them all play again. Like before, they know there are 6 prisoners, 3 red hats and 3 white hats. They know one prisoner is ...
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Guessing hat colors. 4 prisoners
This is a variant about guessing hat colors. You may want to try
Hats and alien or Guessing hat colors or Four prisoners wearing black and white hats.
Statement
4 prisoners are to be executed. The ...
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A harder version of a Richard Hess logical hat problem
In the July/August 2021 issue of MIT Technology Review, there was a "logical hat" problem by Richard Hess in the Puzzle Corner. I noticed that it could be generalized. Here is the "next ...
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Hat guessing without knowing the colors
Generalization of this problem:
Guessing hat colors. 4 prisoners
Suppose that there are $N$ prisoners, instead of $4$. Show, by finding explicitly the strategy, that if $N$ is even there is a strategy ...
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