Question

一头驴突然打嗝，第一次打嗝发生在某天下午 $4:00$ 。假设它每隔 $5$ 秒规律地打一次嗝。它第 $700$ 次打嗝发生在什么时间？

A donkey suffers an attack of hiccups and the first hiccup happens at $4:00$ one afternoon. Suppose that the donkey hiccups regularly every $5$ seconds. At what time does the donkey’s $700$ th hiccup occur?

$4:58$ 后十五秒

15 seconds after $4:58$

$4:58$ 后二十秒

20 seconds after $4:58$

$4:58$ 后二十五秒

25 seconds after $4:58$

$4:58$ 后三十秒

30 seconds after $4:58$

$4:58$ 后三十五秒

35 seconds after $4:58$

答案：A

知识点：等差数列单位换算

难度评级：870

解答：

要求第 $700$ 次打嗝，就要看它比第一次晚了 $699$ 个间隔。

所以时间是 $4:58$ 后 $15$ 秒，因为 $699\cdot 5 = 3495$ ，且 $3495 = 60\cdot 58+15$ ，即经过 $58$ 分 $15$ 秒。

所以答案是 A。

Since we want to look at the $700$ th hiccup, we need to look at time that is $699$ hiccups after the first one.

This would be $699\cdot 5 = 3495$ seconds. Note that $3495 = 60\cdot 58+15,$ so the time would be $58$ minutes and $15$ seconds after the first hiccup. This would therefore be $4:58$ and $15$ seconds.

Thus, the answer is A .

2022 AMC 10B 第 4 题

答案：A

难度评级：870

解答：

其他年份的第 4 题