A passenger car travels from station A to station B at a speed of 80 kilometers per hour, while a freight train travels from station B to station A at a speed of 60 kilometers per hour. After 3.5 hours, the two cars meet. How many kilometers is the length of the railway between A and B?
一列客车以每小时行80千米的速度从甲站开往乙站，同时有一列货车以每小时60千米的速度从乙站开往甲站，经过3.5小时两车相遇．甲乙两站之间的铁路长多少千米？
<gadget id="calculator">80 + 60</gadget>
<output>140</output>

<gadget id="calculator">140 * 3.5</gadget>
<output>490</output>

<result>490</result>