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Octahedron Platonic

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August 17th, 2010 Posted 4:42 pm

Octahedron Platonic
What is the ratio of edge lengths in the platonic solids?

What is the ratio of edge lengths in the platonic solids such that all 5 solids would be the same height when placed flat on a plane?

I ask because I am building models of the 5 platonic solids for an art project and would like them all to be the same size.

For instance, if the edge length on the tetrahedron = 1, then
cube = 0.8
octahedron = 0.6
etc...

Let them all have an arbitrary height of 1. Below are the respective edge lengths:

tetrahedron: √(6) / 2
cube: 1
octahedron: √(6) / 2 (same as the tetrahedron)
dodecahedron: √[50 - 22√(5)] / 2
icosahedron: [3√(3) - √(15)] / 2

Magformers - Octahedron

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