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Stir Your Coffee: One Point Stays Put

However you stir, some drop ends where it started

Stir your coffee as wildly as you like. Could every last drop end up somewhere new?

You'll find out

  • Why some drop never gets away
  • What a map on a floor has to do with it
  • How to find the spot that never moves

Why it matters

It's math you can feel with a spoon, and the same idea quietly settles web rankings.

About 3 min6 interactive slides · 5 questionsLesson 199 · Zone 23

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