# The coin flip conundrum - Po-Shen Loh

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TEDEd Animation

## Let’s Begin…

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.

## If you flip a coin 1001 times, the expected number of consecutive heads-heads occurrences is exactly 250, which is also exactly the same as the expected number of consecutive heads-tails pairs. Why, then, is the expected time until the first consecutive heads-heads occurrence longer?

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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