MathDB
Drilling a Tunnel

Source:

December 28, 2006
geometry3D geometryprismrectangleAMCAIMEanalytic geometry

Problem Statement

Let EFGHEFGH, EFDCEFDC, and EHBCEHBC be three adjacent square faces of a cube, for which EC=8EC=8, and let AA be the eighth vertex of the cube. Let II, JJ, and KK, be the points on EF\overline{EF}, EH\overline{EH}, and EC\overline{EC}, respectively, so that EI=EJ=EK=2EI=EJ=EK=2. A solid SS is obtained by drilling a tunnel through the cube. The sides of the tunnel are planes parallel to AE\overline{AE}, and containing the edges, IJ\overline{IJ}, JK\overline{JK}, and KI\overline{KI}. The surface area of SS, including the walls of the tunnel, is m+npm+n\sqrt{p}, where mm, nn, and pp are positive integers and pp is not divisible by the square of any prime. Find m+n+pm+n+p.