Two trains depart from two places 417 kilometers apart at the same time and meet after 3 hours. It is known that the speed of the fast train is 1.5 times that of the slow train. Ask: How many kilometers does the slow train travel per hour?
两列火车从相距417千米的两地同时开出，3小时后相遇，已知快车的速度是慢车的1.5倍，问：慢车每小时行驶多少千米？
<gadget id="calculator">1 + 1.5</gadget>
<output>2.5</output>

<gadget id="calculator">417 / 3 / 2.5</gadget>
<output>55.6</output>

<result>55.6</result>