Practice more problem-solving at https://brilliant.org/TedEd/

Solution to the bonus riddle mentioned at the end: https://brilliant.org/tededcoinflip

You heard the travelers’ tales, you followed the maps, and now, you’ve finally located the dungeon containing a stash of ancient coins. The good news: the wizard who owns the castle has generously agreed to let you have the coins. The bad news: he’s not quite as generous about letting you leave the dungeon ... unless you solve his puzzle. Can you solve it and get out alive? Lisa Winer shows how.

Lesson by Lisa Winer, animation by Artrake Studio.