Problem:
The figure may be folded along the lines shown to form a number cube. Three number faces come together at each corner of the cube. What is the largest sum of three numbers whose faces come together at a comer?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
Each number will share a comer with every number on the cube except the one on the opposite face. Thus the combinations involving , and cannot occur. Consequently the largest sum is .
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions