A passenger train travels from station A to station B at 72 kilometers per hour. At the same time, a freight train travels from station B to station A at 66 kilometers per hour. The two cars meet at a distance of 15 kilometers from the midpoint. How many kilometers is the distance between the two stations?
一列客车从甲站开往乙站，每小时行72千米，同时，一列货车从乙站开往甲站，每小时行66千米，两车在距中点15千米处相遇，甲、乙两站间的路程是多少千米？
<gadget id="calculator">72 - 66</gadget>
<output>6</output>

<gadget id="calculator">2 / 6</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">72 + 66</gadget>
<output>138</output>

<gadget id="calculator">15 * (1/3) * 138</gadget>
<output>690</output>

<result>690</result>