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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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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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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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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Hat and Earring Guessing Puzzle, with penalty for passing
You are in the final round of a game show with 3,999 other conteseants.
Here is the game: The host has blindfolded you at put a red, green or blue hat and red, green or blue earrings (not necessarily ...
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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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23 people wearing hats with a bell ringing [closed]
24 extremely intelligent people get invited to a really important party. Since it's really important after 9pm (the start time of the party) a guardian will guard the door to enter the party.
All of ...
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2
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Sorting kids by hat colours [duplicate]
I have taken a group of students on a school trip. I want to organise them into two groups and so I have given each one a coloured hat. Some hats are red, while others are blue. Each child can see ...
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3 hats with numbers, where 2 hats sum to the third
I have outlined a puzzle below, and provided two sources which provide answers. I am disputing that the answer provided in the sources is correct, and I am looking for others to validate or invalidate ...
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Save the poor Gingerbreadmen!
The poor gingerbread men want to survive to Xmas (they don't mind being eaten afterwards). If at least one of them doesn't guess his hat correctly, they will all be cruelly eaten before Xmas. This is ...
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Guess the hat colors - Riddle 7
My brother just created this puzzle for me for Halloween, at first I thought it looked simple, but then it turned out to be very challenging (at least for me!) I'll add it to my collection/app soon. I ...
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Guess the hat colors - Riddle 6
And for today, a new original hat guessing puzzle!
CHALLENGE: Guess the hats of the 4 prisoners.
SPECIAL RULE: One of the prisoners is lying
DESCRIPTION: Each one can see the hats that are in front ...
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Ernest does not know the color of his hat (3)
(again a more a difficult one)
The (same) premise:
An unknown number of people stands on a line playing a hat guessing game
they may not move during the game, they can only look straight ahead (each ...
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