The speed of the slow train is that of the express train (5/7). The two trains depart from Station A and Station B at the same time and go towards each other, and meet at a distance of 36 kilometers from the midpoint. How many kilometers did the express train travel when they met?
慢车速度是快车的(5/7)，两车从甲、乙两站同时开出相向而行，在离中点36千米处相遇．相遇时快车行驶了多少千米？
<gadget id="calculator">36 * 2</gadget>
<output>72</output>

<gadget id="calculator">7 - 5</gadget>
<output>2</output>

<gadget id="calculator">72 / 2</gadget>
<output>36</output>

<gadget id="calculator">36 * 7</gadget>
<output>252</output>

<result>252</result>