What kind of logic puzzle is this?

“Counterfeit Coin Puzzle” is a Hard logic puzzle in the logic category on Numerus System.

Yes — you can expand the hint section above the answer. It is optional and designed to nudge your reasoning without spoiling the full solution.

How difficult is this puzzle?

It is marked as Hard. Easy puzzles are quicker; hard ones need more sustained focus.

Where can I find more puzzles like this?

Browse the logic hub for more problems, or scroll to “More logic problems” for related puzzles on this site.

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Counterfeit Coin Puzzle

Hardlogic

This Hard puzzle in the “logic” category rewards careful reading and step-by-step reasoning. Use the hint if you are stuck, then compare your approach with the explained answer.

You have 12 coins. One of them is counterfeit, and it is either heavier or lighter than the others. The remaining 11 coins are identical and genuine.

You have a balance scale and may use it only 3 times.

Can you always determine which coin is counterfeit and whether it is heavier or lighter?

Preparing…

Counterfeit Coin Puzzle

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