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TED-Ed

Can you outsmart Fate and break her ancient curse? - Dan Finkel

1,799,794 Views

1,025 Questions Answered

TEDEd Animation

Let’s Begin…

Hundreds of years ago, your ancestor stole a magical tarot deck from Fate herself— and it came with a terrible cost. Once every 23 years, one member of your family must face Fate in a duel with rules only known to your opponent. And every time, generation after generation, the outcome is the same: Fate claims their soul. Today, it’s your turn. Can you defeat Fate? Dan Finkel shows how.

Additional Resources for you to Explore

The problem posed here is actually a variation of a classic riddle known as the “Tax Collector” problem. The modern version was popularized by Dan Finkel - the author of this riddle - in the New York Times Numberplay blog in 2015. You can read the original puzzle and a discussion of its solution here.

The math educator Raj Shah also made a video posing the problem, available here.

An older version of the problem is discussed in some detail here

The 538 Riddler column riffed on this puzzle as well, with another interesting variation. Read it here.

Practice some variations on the riddle with these problems below:
-What’s the largest sum you could take if you weren’t concerned about getting the 2, 6, or 10? 

-Try playing the game with 24 cards instead of 23. How does the outcome change? Play with larger and smaller decks (i.e., 12 cards, or 40 cards). Do larger decks tend to favor you, or favor Fate? Is there any number of cards that would be unwinnable for you?

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Meet The Creators

Educator
Daniel Finkel
Director
Igor Coric, Artrake Studio
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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