The highway between A and B is 504 kilometers long, and passenger cars and trucks depart from A and B respectively at the same time. The speed of the passenger car is 1.4 times that of the truck, and the two cars meet each other 3.5 hours after departure. How many miles does the truck travel per hour? (Solution of column equation)
甲乙两城间的公路长504千米，客车与货车同时分别从甲、乙两城出发．客车的速度是货车的1.4倍，出发后3.5小时两车相遇．货车每小时行多少千米？(列方程解)
<gadget id="calculator">1.4 * 3.5</gadget>
<output>4.9</output>

<gadget id="calculator">4.9 + 3.5</gadget>
<output>8.4</output>

<gadget id="calculator">504 / 8.4</gadget>
<output>60</output>

<result>60</result>