Golden Ratios
The golden ratio in a pentagram for geometers, and for parents the 'golden' ratio of siblings' shares is exactly 1.
Use this cartoon
Free for classrooms, worksheets, slides and other non-commercial use under CC BY-NC 4.0, with credit to Ben Orlin.
Cartoon by Ben Orlin, Math with Bad Drawings. https://cartoons.mathwithbaddrawings.com/2019-03-07-golden-ratios/ (CC BY-NC 4.0)Transcript
[Golden Ratio for Geometers] A pentagram with segments 1, φ, φ², φ³; φ = (1 + √5)/2 ≈ 1.618
[Golden Ratio for Parents] Parent: "Either share equally, or no one gets anything!" φ = Sibling #1's share / Sibling #2's share = 1