An ancient monarch wants to test three advisors. He places a random colored hat—either red or blue—on each advisor's head. Each advisor can see the other two hats but not their own. They are told that at least one hat is red. If an advisor steps forward and correctly names their own hat color, they win. If they guess wrong, they are banished. After a minute of silence, all three step forward simultaneously and announce their hats are red. How did they deduce this?
Each advisor reasoned that if the other two were wearing blue, the remaining person would see two blues and immediately know their own hat was red (since there must be at least one red). Because no one spoke instantly, at least one other person must be wearing red. Extending this logic, all three realized their hats were red.
This is a classic variation of the muddy children / three hats puzzle solved through simultaneous elimination of the impossible scenario where too few red hats exist.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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