Question

AMC 所在的 Nebraska 改变了车牌方案。旧车牌由一个字母后接四个数字组成；新车牌由三个字母后接三个数字组成。可能车牌数增加为原来的多少倍？

Nebraska, the home of the AMC, changed its license plate scheme. Each old license plate consisted of a letter followed by four digits. Each new license plate consists of three letters followed by three digits. By how many times is the number of possible license plates increased?

$\dfrac{26}{10}$

$\dfrac{26^2}{10^2}$

$\dfrac{26^2}{10}$

$\dfrac{26^3}{10^3}$

$\dfrac{26^3}{10^2}$

答案：C

知识点：乘法原理比与比例

难度评级：1170

解答：

旧方案有 $26 \cdot 10^4$ 种车牌，新方案有 $26^3 \cdot 10^3$ 种。增加倍数为 $\dfrac{26^3 \cdot 10^3}{26 \cdot 10^4}=\dfrac{26^2}{10}.$

所以正确答案是 C。

The old scheme allows $26 \cdot 10^4$ plates and the new scheme allows $26^3 \cdot 10^3$ plates. The increase factor is $\dfrac{26^3 \cdot 10^3}{26 \cdot 10^4}=\dfrac{26^2}{10}.$

Thus, the correct answer is C.

2003 AMC 10B 第 10 题

答案：C

难度评级：1170

解答：

其他年份的第 10 题