1988 AMC 12 第 3 题

Question

四条长

10

、宽

1

的矩形纸条平放在桌面上，并按图示方式两两垂直交叠。桌面上被覆盖的面积是多少？

Four rectangular paper strips of length

10

and width

1

are put flat on a table and overlap perpendicularly as shown. How much area of the table is covered?

36

40

44

98

100

先将四条纸条的面积相加

First add the areas of the four strips

每个垂直交叠处都是一个被重复计算的单位正方形

Each perpendicular crossing is a unit square counted twice

四条纸条的总面积为

4(10)=40

。共有四个

1

乘

1

的交叠区域，每个都被计算了两次，所以覆盖面积为

40-4=36

。

所以正确答案是 A。

The strips have total area

4(10)=40.

There are four

1

-by-

1

overlaps, each counted twice, so the covered area is

40-4=36.

Thus the correct answer is A.

其他年份的第 3 题