Question

NASA 的 Perseverance 探测车于 $2020$ 年七月 $30$ 日发射。它行进 $292,526,838$ 英里后，约 $6.5$ 个月后降落在火星的 Jezero 陨石坑。下列哪一项最接近探测车的平均星际速度，单位为英里每小时？

NASA's Perseverance Rover was launched on July $30,$ $2020.$ After traveling $292,526,838$ miles, it landed on Mars in Jezero Crater about $6.5$ months later. Which of the following is closest to the Rover's average interplanetary speed in miles per hour?

$6,000$

$12,000$

$60,000$

$120,000$

$600,000$

答案：C

知识点：路程、速度与时间估算单位换算

难度评级：1100

视频讲解：

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文字解答：

把距离近似为 $300,000,000$ 英里。把 $6.5$ 个月近似为天，因此每天约行进英里。再除以 $24$ 小时，约为 $62,500$ 英里每小时，最接近 $60,000$ 。 $30 \times 6.5 = 195 \approx 200$ $300,000,000 \div 200 = 1,500,000$

所以正确答案是 C。

We can round the distance up to $300,000,000$ miles. We can also approximate $6.5$ months as $30 \times 6.5 = 195 \approx 200$ days. This means that the Rover traveled $300,000,000 \div 200 = 1,500,000$ miles per day. Dividing this by $24$ to get the speed in miles per hour yields $62,500,$ which is close to $60,000.$

Thus, C is the correct answer.

2023 AMC 8 第 11 题

答案：C

难度评级：1100

视频讲解：

文字解答：

其他年份的第 11 题