MathDB
Faces Of Cube

Source:

June 27, 2011
geometry3D geometry

Problem Statement

The numbers on the faces of this cube are consecutive whole numbers. The sums of the two numbers on each of the three pairs of opposite faces are equal. The sum of the six numbers on this cube is
[asy] draw((0,0)--(3,0)--(3,3)--(0,3)--cycle); draw((3,0)--(5,2)--(5,5)--(2,5)--(0,3)); draw((3,3)--(5,5)); label("1515",(1.5,1.2),N); label("1111",(4,2.3),N); label("1414",(2.5,3.7),N);[/asy]
(A) 75(B) 76(C) 78(D) 80(E) 81 \text{(A)}\ 75\qquad\text{(B)}\ 76\qquad\text{(C)}\ 78\qquad\text{(D)}\ 80\qquad\text{(E)}\ 81