1955 AMC 12 第 7 题

Question

若一名工人的工资降低

20

%，那么要恰好恢复到原工资，他需要获得多大幅度的加薪？

If a worker receives a

20

percent cut in wages, he may regain his original pay exactly by obtaining a raise of:

20

%

20

percent

25

%

25

percent

22\dfrac12

%

22\dfrac12

percent

\$20

\$25

降薪后，工资是原来的

80\%

After the cut, the wage is

80\%

of the original

求原工资少掉的

20\%

占降薪后工资的百分比

Find the percent of the reduced wage represented by the missing

20\%

of the original

若原工资为

W

，则降薪后的工资为

0.8W

。所需增加额为

0.2W

，它占降薪后工资的比例为

\frac{0.2W}{0.8W}=\frac14=25\%\text{。}

因此，正确答案是 B。

If the original wage is

W,

the reduced wage is

0.8W.

The needed increase is

0.2W,

which as a fraction of the reduced wage is

\frac{0.2W}{0.8W}=\frac14=25\%.

Thus, the correct answer is B.

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