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The Kid Should See This

Can you solve the fortress riddle?

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“Bad news: your worst enemies are at the gate. Your fledgling kingdom guards the world’s only herd of tiny dino creatures. To you, they’re sacred. To everyone else, they’re food. The three closest nation-states have teamed up to smash open your walls and devour the herd. Can you build fortifications for your kingdom before the siege weapons arrive?”

How can you use math and logic to protect your tiny dinos from becoming dinner for the other three kingdoms? Watch this Fortress Riddle TED-Ed video by Henri Picciotto, with direction by Igor Coric of Artrake Studio.

Pause the video at the 2m5s mark to try and figure the puzzle out without help. The solution is shared in the second half of the video.

Related exploration: The Coin Problem and the Sieve of Eratosthenes. Or try this challenge next: The McNuggets Problem (pdf).

Watch more math-related TED-Ed videos next:
• Can you solve the monster duel riddle?
• Can you solve the wizard standoff riddle?
• Can you solve the virus riddle?
Can you solve the unstoppable blob riddle?

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