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The coin flip conundrum - Po-Shen Loh

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TEDEd Animation

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When you flip a coin to make a decision, there's an equal chance of getting heads and tails. What if you flipped two coins repeatedly, so that one option would win as soon as two heads showed up in a row on that coin, and one option would win as soon as heads was immediately followed by tails on the other? Would each option still have an equal chance? Po-Shen Loh describes the counterintuitive math behind this question.

Suppose Orville and Wilbur are flipping a single coin, and as soon as heads is immediately followed by heads, Orville wins. But as soon as there is heads immediately followed by tails, Wilbur wins. Who has the better chance of winning?

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Meet The Creators

  • Educator Po-Shen Loh
  • Director Mimi Chiu
  • Script Editor Eleanor Nelsen
  • Producer Aaron Augenblick
  • Animator Mimi Chiu
  • Collaborator Andrea Janov , Zach Nelkin, Mark Paulson
  • Associate Producer Elizabeth Cox, Jessica Ruby
  • Content Producer Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Narrator Addison Anderson
  • Fact-Checker Brian Gutierrez

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