The length of the railway between A and B is 460 km. A passenger train runs from station A to station B at a speed of 80 kilometers per hour, and a freight train travels from station B to station A at a speed of 35 kilometers per hour. After how many hours do the two cars meet?
甲乙两站之间的铁路长460千米．一列客车以每小时80千米的速度从甲站开往乙站，同时一列货车一每小时35千米的速度从乙站开往甲站，经过几小时两车相遇？
<gadget id="calculator">80 + 35</gadget>
<output>115</output>

<gadget id="calculator">460 / 115</gadget>
<output>4</output>

<result>4</result>