Solved cryptogram
A ball cannot be tiled with hexagons alone. A soccer ball needs a dozen pentagons as well.
Mathematics Facts, sourced to Wolfram MathWorld.
Solve it yourself
This fact is a cryptogram here: 72 letters over 18 different ones, graded easy.
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What it means
The classic ball is twenty hexagons and twelve pentagons, and the twelve is not a design choice. Hexagons tile a flat sheet perfectly and that is the problem: a sheet that stays flat cannot close into a ball. Introducing a pentagon puts a small cone of curvature into the surface, and Euler's formula fixes the number needed at exactly twelve. The same arithmetic governs the carbon cage of buckminsterfullerene.
The claim comes from Wolfram MathWorld.
- SourceWolfram MathWorld
- CollectionMathematics Facts
- Difficultyeasy
- Length72 letters, 18 of them different
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