It takes 5 hours for a bus to travel from station A to station B, and 7 hours for a truck to travel from station B to station A. Two cars depart from Station A and Station B at the same time and meet at a distance of 35 kilometers from the midpoint of the two stations. What is the distance in kilometers between stations A and B?
一辆客车从甲站开往乙站需要5小时，一辆货车从乙站开往甲站需要7小时．两车同时从甲、乙两站相对开出，在离两站中点35千米处相遇．求甲、乙两站相距多少千米？
<gadget id="calculator">7 - 5</gadget>
<output>2</output>

<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">5 + 7</gadget>
<output>12</output>

<gadget id="calculator">35 * 1 * 12</gadget>
<output>420</output>

<result>420</result>