AMC12 2020 B

AMC12 2020 B · Q3

AMC12 2020 B · Q3. It mainly tests Ratios & proportions.

The ratio of $w$ to $x$ is $4 : 3$, the ratio of $y$ to $z$ is $3 : 2$, and the ratio of $z$ to $x$ is $1 : 6$. What is the ratio of $w$ to $y$?

$w$ 与 $x$ 的比为 $4 : 3$，$y$ 与 $z$ 的比为 $3 : 2$，$z$ 与 $x$ 的比为 $1 : 6$。$w$ 与 $y$ 的比是多少？

(A) 4 : 3 4 : 3

(B) 3 : 2 3 : 2

(D) 4 : 1 4 : 1

(E) 16 : 3 16 : 3

Answer

Correct choice: (E)

正确答案：（E）

Solution

Because $\frac{w}{y} = \frac{w}{x} \cdot \frac{x}{z} \cdot \frac{z}{y} = \frac{4}{3} \cdot 6 \cdot \frac{2}{3} = \frac{16}{3}$, the requested ratio is $16:3$.

因为 $\frac{w}{y} = \frac{w}{x} \cdot \frac{x}{z} \cdot \frac{z}{y} = \frac{4}{3} \cdot 6 \cdot \frac{2}{3} = \frac{16}{3}$，所求比为 $16:3$。

Topics

AR.004 Ratios & proportions