MathDB
Coaxial right circular conical frustums

Source: Czech and Slovak Olympiad 1959, National Round, Problem 3

June 14, 2024
geometry3D geometryfrustum

Problem Statement

Consider a piece of material in the shape of a right circular conical frustum with radii R,r,R>rR,r,R>r. A cavity in the shape of another coaxial right circular conical frustum was drilled into the material (see the picture). That way only half of the original volume of material remained. Compute radii R,rR',r' of the cavity. Decide for which ratio R/rR/r the problem has a solution. https://cdn.artofproblemsolving.com/attachments/b/f/12f579458b7cf0fc31849b319e6f58e50b0363.png