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1985 AJHSME Problems/Problem 11

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Problem

A piece of paper containing six joined squares labeled as shown in the diagram is folded along the edges of the squares to form a cube. The label of the face opposite the face labeled \text{X} is

draw((0,0)--(0,1)--(2,1)--(2,2)--(3,2)--(3,0)--(2,0)--(2,-2)--(1,-2)--(1,0)--cycle);draw((1,0)--(1,1));draw((2,0)--(2,1));dra...

\text{(A)}\ \text{Z} \qquad \text{(B)}\ \text{U} \qquad \text{(C)}\ \text{V} \qquad \text{(D)}\ \ \text{Y} \qquad \text{(E)}\...

Solution

To find the face opposite \text{X}, we can find the faces sharing an edge with \text{X}, so the only face remaining will be the opposite face.

Clearly, \text{V} and \text{Z} share an edge with \text{X}. Also, the faces \text{V}, \text{X}, and \text{W} share a common vertex, therefore \text{X} shares an edge with \text{W}. Similarly, the faces \text{U}, \text{V}, and \text{X} share a common vertex, so \text{X} shares an edge with \text{W}.

The only face \text{X} doesn't share an edge with is \text{Y}, which is choice \boxed{\text{D}}

See Also

1985 AJHSME (ProblemsResources)
Preceded by
Problem 10
Followed by
Problem 12
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