The length of the railway between A and B is 850 km. A train of passenger cars and a train of freight trains leave from two places at the same time. The passenger train travels 92 kilometers per hour, and the freight train travels 78 kilometers per hour. After how many hours did the two cars meet on the way?
甲、乙两地间的铁路长850千米．一列客车和一列货车同时从两地相对开出，客车每小时行92千米，货车每小时行78千米．经过几小时两车在途中相遇？
<gadget id="calculator">92 + 78</gadget>
<output>170</output>

<gadget id="calculator">850 / 170</gadget>
<output>5</output>

<result>5</result>