# Circular Cone

Author(s):

Given the frustum of a circular cone with height h.  The areas of its bases are known: A1 and A2.  Find an expression for the height at which this frustum must be cut to produce a cross section area A3 where A3 is the mean proportional between A1 and A2.

Leonardo of Pisa, Practica geometriae, 1220

"Circular Cone," Loci (March 2007)