1955 AMC 12 第 23 题

Question

一名职员清点零用现金时，数得

q

枚二十五美分硬币、

d

枚十美分硬币、

n

枚五美分硬币和

c

枚一美分硬币。后来他发现，有

x

枚五美分硬币被当作二十五美分硬币，又有

x

枚十美分硬币被当作一美分硬币。要更正所得总额，他必须：

In checking the petty cash a clerk counts

q

quarters,

d

dimes,

n

nickels, and

c

cents. Later he discovers that

x

of the nickels were counted as quarters and

x

of the dimes were counted as cents. To correct the total obtained the clerk must:

不作更正

make no correction

减去

11

¢

subtract

11

¢

减去

11x

¢

subtract

11x

¢

加上

11x

¢

add

11x

¢

加上

x

¢

add

x

¢

答案：C

知识点：coin values accounting error linear expression

难度评级：1280

小提示：

每把一枚五美分硬币当作二十五美分硬币，总额就会多算

20

¢

Each nickel counted as a quarter makes the total too large by

20

¢

大提示：

每把一枚十美分硬币当作一美分硬币，总额就会少算

9

¢

Each dime counted as a cent makes the total too small by

9

¢

解答：

把

x

枚五美分硬币当作二十五美分硬币，使总额多算

20x

¢。把

x

枚十美分硬币当作一美分硬币，使总额少算

9x

¢。因此净多算了

20x-9x=11x

美分，必须减去这个数额。

因此，正确答案是 C。

The

x

nickels counted as quarters overstate the total by

20x

¢. The

x

dimes counted as cents understate it by

9x

¢. The net overstatement is

20x-9x=11x

cents, so that amount must be subtracted.

Thus, the correct answer is C.

1955 AMC 12 第 23 题

答案：C

难度评级：1280

小提示：

大提示：

解答：

其他年份的第 23 题