MathDB

11

Part of 1990 AMC 8

Problems(1)

Faces Of Cube

Source:

6/27/2011
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
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