AMC 8 1999 Problem 8
AMC8 1999 年第 8 题
立体几何★★☆☆☆
Six squares are colored, front and back, (R = red, B = blue, O = orange, Y = yellow, G = green, and W = white). They are hinged together as shown, then folded to form a cube. The face opposite the white face is
六个正方形，正面和背面分别涂有颜色（R = 红色，B = 蓝色，O = 橙色，Y = 黄色，G = 绿色，W = 白色）。它们如图所示铰接在一起，然后折叠形成一个正方体。白色面相对的面颜色是什么？
- A.B
- B.G
- C.O
- D.R
- E.Y
正确答案 · Correct Answer
A
解析 · Solution
Solution 1
When G is arranged to be the base, B is the back face and W is the front face. Thus, is opposite W.
Let Y be the top and fold G, O, and W down. Then will fold to become the back face and be opposite W.
If you're out of time or checking your work, I guess you can just rip a net from some paper (no scissors though). Like I said, this is a last resort and not very convenient. would be the answer.
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