It takes 10 hours for car A to drive from station A to station B, and it takes 15 hours for car B to drive from station B to station A. The two cars leave opposite directions at the same time and meet at a distance of 40 kilometers from the midpoint. How many kilometers are the distance between the two stations.
甲车从A站开往B站需10小时，乙车从B站开往A站需15小时，两车同时从两站相向开出，距中点40千米处相遇．两站相距多少千米．
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / (1/6)</gadget>
<output>6</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">6 - 5</gadget>
<output>1</output>

<gadget id="calculator">40 / 1</gadget>
<output>40</output>

<gadget id="calculator">40 * 10</gadget>
<output>400</output>

<result>400</result>