Problem:
All six sides of a rectangular solid were rectangles. A one-foot cube was cut out of the rectangular solid as shown. The total number of square feet in the surface of the new solid is how many more or less than that of the original solid?
Answer Choices:
A. less
B. less
C. the same
D. more
E. more
Solution:
When the one-foot cube is removed, three square feet of surface area are "removed", but three new square feet of surface area are "uncovered". Thus, the original surface area is unchanged.
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions