Euclid's Elements - Book 8, Proposition 19

Proposition: If A,B are similar solid numbers, A=CDE, B = FGH and C:D=F:G and D:E=G:H, then A:B is the triplicate ratio of C:F, D:G, E:H, and there are two mean numbers between A and B PDFs: https://github.com/sandy-bultena/Eucl...