Figure out the number I'm thinking of with a single question!
I'm thinking of a number amongst 1, 2, and 3. You are allowed to ask me a single question, to which I will truthfully answer with “yes”, “no”, or “I don't know”.
How can you find out the number I picked?
Give it some thought!
If you need any clarification whatsoever, feel free to ask in the comment section below.
(I originally found this puzzle on Reddit.)
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Congratulations to the ones that solved this problem correctly and, in particular, to the ones who sent me their correct solutions:
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Lots of people sent in their solutions and I was very pleased with the amount of different solutions people came up with! Hence, the solution I present here is not the only one, but it's one I find very elegant.
The question you will ask me is
“If I pick one of the other two numbers, is yours larger?”
If I picked 3, then I know 3 is larger than any of the two other numbers (1 and 2). Therefore, I answer “Yes.”.
If I picked 1, then I know 1 is smaller than any of the two other numbers (2 and 3). Therefore, I answer “No.”.
If I picked 2, then I have no idea if you got 1 or 3, and that implies I need to reply “I don't know.”.
That's a pretty elegant solution, isn't it?
Feel free to share alternative solutions in the comments!
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