Regular Dodecahedron is Dual of Regular Icosahedron/Mistake

Source Work

1986: David Wells: Curious and Interesting Numbers:

The Dictionary

$30$

1997: David Wells: Curious and Interesting Numbers (2nd ed.):

The Dictionary

$30$

Mistake

The dodecahedron and its dual, the icosahedron, each have $30$ edges.

Correction

It is important not to neglect the crucial point that both figures must be regular.

Otherwise, for example, consider the dodecahedron which is the bipyramid consisting of two hexagonal pyramids placed base to base.

Its dual is the hexagonal prism, which has $8$ faces, and so is not an icosahedron at all.

Sources

• 1986: David Wells: Curious and Interesting Numbers ... (previous) ... (next): $30$
• 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $30$