The diameter of the driving wheel of a train is 1.2 meters. If it turns 400 times per minute, how many meters can it travel per hour?
一列火车的主动轮直径是1.2米，如果每分钟转400圈，每小时可以行多少米？
<gadget id="calculator">3.14 * 1.2 * 400 * 60</gadget>
<output>90_432</output>

<result>90_432</result>