A circular runway with a total length of 700 meters. A and B set off from the same place at the same time and walk opposite each other. A runs 7.5 meters per second, and B runs 6.5 meters per second. After a few seconds, the two meet?
一个圆形跑道，全长700米．甲乙两人同时同地出发，相背而行．甲每秒钟跑7.5米，乙每秒跑6.5米，几秒钟后两人相遇？
<gadget id="calculator">7.5 + 6.5</gadget>
<output>14</output>

<gadget id="calculator">700 / 14</gadget>
<output>50</output>

<result>50</result>