Question

一张长方形照片放入相框后，照片四周形成宽二英寸的边框。照片高 $8$ 英寸、宽 $10$ 英寸。边框的面积是多少平方英寸？

A rectangular photograph is placed in a frame that forms a border two inches wide on all sides of the photograph. The photograph measures $8$ inches high and $10$ inches wide. What is the area of the border, in square inches?

$36$

$40$

$64$

$72$

$88$

答案：E

知识点：面积矩形

难度评级：820

视频讲解：

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文字解答：

每一边都增加 $2$ 英寸，所以高度和宽度各总共增加 $4$ 英寸。外部长方形尺寸为 $12 \times 14$ ，面积为 $12\cdot 14 = 168$ 。

照片本身面积为 $8 \cdot 10 =80$ 。

因此边框面积为 $168-80=88$ 。

所以正确答案是 E。

If we add $2$ inches on each side, we add $4$ inches total on both sides. This means that the dimensions of the outer part of the frame are $12 \times 14.$ The area of this is $12\cdot 14 = 168.$

However, we must take out the area of the inner part of the frame which has area $8 \cdot 10 =80.$

Therefore, the total area is $168-80=88.$

Thus, the answer is E .

2012 AMC 8 第 6 题

答案：E

难度评级：820

视频讲解：

文字解答：

其他年份的第 6 题