Can you identify a single counterfeit coin to win your freedom?

Ideas & Philosophy · Published 8 October 2026 Swipe more like this →

In short: Imagine you are a mathematician imprisoned by an Emperor. To earn your release, you must use logic to find one fake coin hidden within the imperial treasury.

In this animated lesson, Jennifer Lu demonstrates the mathematical approach to solving the counterfeit coin riddle. The challenge requires identifying a fraudulent coin that has entered the treasury via a convicted governor's tax payment.

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