Townspeople are demanding that a corrupt merchant’s collection of 30 rubies be confiscated to reimburse the victims of his schemes. The king announces that the fine will be determined through a game of wits between the merchant and the king’s most clever advisor – you. Can you outfox the merchant and win back the greatest amount of rubies to help his victims?

Learn how to solve the stolen rubies riddle, a TED-Ed lesson by Dennis Shasha, but try solving it first. Pause for the rules of the riddle at 2m4s:

stolen rubies riddle
And here’s the sponsored solution to the bonus riddle.

To practice solving more math puzzles, TED-Ed recommends this book by Shasha: The Puzzling Adventures of Dr. Ecco. We also highly recommend the One Minute Mysteries Book Series in the TKSST Gift Guide.

Then try solving the dark coin riddle, the Leonardo da Vinci riddle, and the wizard standoff riddle next.

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