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comment by elizabeth
elizabeth  ·  3407 days ago  ·  link  ·    ·  parent  ·  post: My favourite math puzzle

Does the Guru sees only one person with blue eyes or at least one?

If the Guru sees only one person with blue eyes, each goes one by one to look from the perspective of the Guru. If they don't see anyone with blue eyes, it means it's them. If they see the blue-eyes person, they know they have green eyes. Everyone in the room at that moment leaves the island.

If more than one person has blue eyes, it does not work tho.

Also, I know you said there is not trick but if there were, you could assume that by saying "I can see someone who has blue eyes" the Guru means that green eyes people are invisible to her. If the guru can see you, you thus have blue eyes :P (Bullshit answer, I know it's not this)





yakov  ·  3407 days ago  ·  link  ·  

At least one. And other eye colors are allowed, not just blue and green.

Yeah, there's really no trick. When you get the solution you'll know.