Mind-Bending Math & GamesCombinatorics
The Pigeonhole Trick
Too many pigeons for the holes guarantees a hidden match
Thirteen strangers walk into a room. Without asking a single question, you can prove two were born in the same month.
You'll find out
- How to prove it without asking anyone
- What the trick can never tell you
- What hair has to do with it
Why it matters
The same simple counting proves that no zip app can shrink every file, however clever its code.
Play this lesson
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