AMC 8 1989 Problem 23

AMC8 1989 年第 23 题

立体几何★★★☆☆
An artist has 14 cubes, each with an edge of 1 meter. She stands them on the ground to form a sculpture as shown. She then paints the exposed surface of the sculpture. How many square meters does she paint?
一位艺术家有 14 个棱长为 1 米的正方体。她将它们立在地上形成如图所示的雕塑。然后她对雕塑的暴露表面进行涂漆。她涂了多少平方米?
AMC 8 1989 Problem 23 figure
  1. A.21
  2. B.24
  3. C.33
  4. D.37
  5. E.42

正确答案 · Correct Answer

C

解析 · Solution

Solution 1

The top view of this figure forms a 3 m×3 m3\text{ m} \times 3\text{ m} square, so it has area 9 m29\text{ m}^2.
The left, right, front, and rear views each consist of six 1 m×1 m1\text{ m} \times 1\text{ m} squares stacked in a pyramid shape, so each of these views has an area of 6 m26\text{ m}^2. So, these views have a total area of 4⋅6=24 m24 \cdot 6 = 24 \text{ m}^2.
Therefore, the total painted area is 9+24=33 m29 + 24 = 33 \text{ m}^2. Note that the bottom is not painted.

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