AMC10 2014 B

AMC10 2014 B · Q7

AMC10 2014 B · Q7. It mainly tests Percent.

Suppose $A > B > 0$ and $A$ is $x\%$ greater than $B$. What is $x$?

假设 $A > B > 0$，且 $A$ 比 $B$ 大 $x\%$。$x$ 是多少？

(A) $100\frac{A-B}{B}$ $100\frac{A-B}{B}$

(B) $100\frac{A+B}{B}$ $100\frac{A+B}{B}$

(D) $100\frac{A-B}{A}$ $100\frac{A-B}{A}$

(E) $100\frac{A}{B}$ $100\frac{A}{B}$

Answer

Correct choice: (A)

正确答案：（A）

Solution

The fraction by which $A$ is greater than $B$ is simply the positive difference $(A - B)$ divided by $B$. The percent difference is 100 times this, or $100\frac{A-B}{B}$.

A 比 B 大的分数就是正差 $(A - B)$ 除以 $B$。百分比差就是这个值的 100 倍，即 $100\frac{A-B}{B}$。

Topics

AR.003 Percent