The outer tire diameter of a car is 9 decimeters, and the wheels roll 1000 times per minute. How many kilometers does this car travel per hour?
一辆汽车的外轮胎直径是9分米，车轮每分钟滚动1000周，这辆车每小时前进多才千米？
<gadget id="calculator">60 / 10_000</gadget>
<output>3/500 = around 0.006</output>

<gadget id="calculator">3.14 * 9 * 1_000 * 1 * (3/500)</gadget>
<output>169.56</output>

<result>169.56</result>