Question

一份可做 $5$ 份热巧克力的食谱需要 $2$ 块巧克力、 $\dfrac{1}{4}$ 杯糖、 $1$ 杯水和 $4$ 杯牛奶。Jordan 有 $5$ 块巧克力、 $2$ 杯糖、很多水和 $7$ 杯牛奶。如果她保持相同的配料比例，最多能做多少份热巧克力？

A recipe that makes $5$ servings of hot chocolate requires $2$ squares of chocolate, $\dfrac{1}{4}$ cup sugar, $1$ cup water and $4$ cups milk. Jordan has $5$ squares of chocolate, $2$ cups of sugar, lots of water, and $7$ cups of milk. If she maintains the same ratio of ingredients, what is the greatest number of servings of hot chocolate she can make?

$5 \dfrac{1}{8}$

$6 \dfrac{1}{4}$

$7 \dfrac{1}{2}$

$8 \dfrac{3}{4}$

$9 \dfrac{7}{8}$

答案：D

知识点：比与比例

难度评级：1220

解答：

需要找出哪种配料是限制因素。

Jordan 的巧克力足够做 $5\div2=\dfrac{5}{2}$ 批，糖足够做 $2\div\dfrac{1}{4}=8$ 批，牛奶足够做 $7\div4=\dfrac{7}{4}$ 批。

牛奶是限制因素，所以 Jordan 可以做 $5\cdot\dfrac{7}{4}=\dfrac{35}{4}=8\dfrac{3}{4}$ 份。

所以正确答案是 D。

We need to find which ingredient is the limiting factor.

Jordan has enough chocolate for $5\div2=\dfrac{5}{2}$ batches, enough sugar for $2\div\dfrac{1}{4}=8$ batches, and enough milk for $7\div4=\dfrac{7}{4}$ batches.

The milk is limiting, so Jordan can make $5\cdot\dfrac{7}{4}=\dfrac{35}{4}=8\dfrac{3}{4}$ servings.

Thus, D is the correct answer.

2009 AMC 8 第 15 题

答案：D

难度评级：1220

解答：

其他年份的第 15 题