AMC 8 1991 Problem 15
AMC8 1991 年第 15 题
立体几何★★★☆☆
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?
一个长方体的六个面都是矩形。如图所示，从该长方体中切掉一个一英尺的正方体。新立体表面的总平方英尺数比原立体多还是少多少？
- A. / 少 2
- B. / 少 1
- C. / 相同
- D. / 多 1
- E. / 多 2
正确答案 · Correct Answer
C
解析 · Solution
Solution 1
Initially, that one-foot cube contributed 3 faces to the surface area of the whole solid. When it was removed, these 3 faces are removed, but there are 3 new faces where the cube was carved out, so the net change is .
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