2011 AMC 12A 第 2 题

Question

有

5

枚硬币按图示平放在桌上。按从上到下的顺序，这些硬币应怎样排列？

There are

5

coins placed flat on a table according to the figure. What is the order of the coins from top to bottom?

(C, A, E, D, B)

(C, A, D, E, B)

(C, D, E, A, B)

(C, E, A, D, B)

(C, E, D, A, B)

轮廓完整、没有被打断的硬币在最上面

A coin whose outline is a complete, unbroken circle lies on top

在每个重叠处，弧线没有被打断的那枚硬币在上方

At each overlap, the coin whose arc is drawn without interruption is the higher one

硬币

C

画成一个完整且没有中断的圆，所以没有东西盖住它，它在最上面。

继续观察其余重叠处，未被遮住的弧线显示每枚硬币在下一枚硬币上方：

C

盖住

E

，

E

盖住

D

，

D

盖住

B

而

A

盖住

B

，同时在其他硬币下方。因此从上到下的顺序是

(C, E, D, A, B)

。

因此，正确答案是 E。

Coin

C

is drawn as a complete, unbroken circle, so nothing covers it and it lies on top.

Reading the remaining overlaps, each coin’s uncovered arc shows it sits above the next:

C

covers

E,

E

covers

D,

D

covers

B,

and

A

covers

B

while lying under the others. This gives the top-to-bottom order

(C, E, D, A, B).

Thus, the correct answer is E.

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