2023 AMC 10B 第 1 题

Question

Jones 太太正在把橙汁倒入四个相同的杯子，给她的四个儿子喝。她把前三个杯子都倒满了，但橙汁用完时，第四个杯子只倒了

\frac{1}{3}

。Jones 太太需要从前三个杯子中的每个杯子倒出几分之一个杯子的橙汁到第四个杯子里，才能使四个杯子中的橙汁量相同？

Mrs. Jones is pouring orange juice into four identical glasses for her four sons. She fills the first three glasses completely but runs out of juice when the fourth glass is only

\frac{1}{3}

full. What fraction of a glass must Mrs. Jones pour from each of the first three glasses into the fourth glass so that all four glasses will have the same amount of juice?

\dfrac{1}{12}

\dfrac{1}{4}

\dfrac{1}{6}

\dfrac{1}{8}

\dfrac{2}{9}

答案：C

知识点：分数

难度评级：860

小提示：

先求橙汁总量，再平均分到四个杯子中。

Find the total amount of juice, then divide it equally among the four glasses

大提示：

每个满杯最终到达公共液面，所以它倒出的量是

1

减去该液面高度。

Each full glass ends at the common level, so it must pour out

1

minus that level

解答：

总共有

3 + \frac{1}{3} = \frac{10}{3}

杯橙汁。平均分到四个杯子中，每杯为

\frac{10}{3} \div 4 = \frac{5}{6}

。因此每个满杯需要倒出

1 - \frac{5}{6} = \frac{1}{6}

杯。所以正确答案是 C。

There’s

3 + \frac{1}{3} = \frac{10}{3}

glasses of juice in all. Split four ways, each glass ends up with

\frac{10}{3} \div 4 = \frac{5}{6}.

So a full glass has to pour out

1 - \frac{5}{6} = \frac{1}{6}.

Thus, C is the correct answer.

2023 AMC 10B 第 1 题

答案：C

难度评级：860

小提示：

大提示：

解答：

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