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This one weird trick will get you infinite gold - Dan Finkel

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  • 479 Questions Answered
  • TEDEd Animation

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A few years ago, the king decided your life would be forfeit unless you tripled the gold coins in his treasury. Fortunately, a strange little man appeared and magically performed the feat. Unfortunately, you promised him your first-born child in exchange for his help — and today he’s come to collect. Can you figure out how to outsmart the man and keep your baby? Dan Finkel shows how.


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Meet The Creators

  • Educator Daniel Finkel
  • Director Gavin Edwards, Movult
  • Narrator Addison Anderson
  • Music Cem Misirlioglu
  • Sound Designer Cem Misirlioglu
  • Senior Producer Anna Bechtol
  • Producer Sazia Afrin
  • Editorial Director Alex Rosenthal
Additional Resources for you to Explore
There are many ways to generalize this situation. Here are a few:

-What would the magic do to 17 coins? To 23? To 30?

-Is it possible to end up with any number of coins after applying the magic once? For example, if I want the bag to hold exactly 47 coins, is there a number I can put in first that will end up with 47 coming out?

-Can you write a formula or description for how the magic behaves?

-What if the bag quadrupled the coins when you applied it three times. Could you find what would happen to 13 coins in this case? Does this situation generalize?

For more on the basics of functions, check out this video from Khan Academy.
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Customize this lesson

Create and share a new lesson based on this one.

About TED-Ed Animations

TED-Ed Animations feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed Animation? Nominate yourself here »

Meet The Creators

  • Educator Daniel Finkel
  • Director Gavin Edwards, Movult
  • Narrator Addison Anderson
  • Music Cem Misirlioglu
  • Sound Designer Cem Misirlioglu
  • Senior Producer Anna Bechtol
  • Producer Sazia Afrin
  • Editorial Director Alex Rosenthal

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