A 50-meter-long train travels through a 200-meter cave in 25 seconds. How many meters does the train travel per second?
一列长50米的火车，穿过200米的山洞用25秒钟，这列火车每秒行多少米？
<gadget id="calculator">50 + 200</gadget>
<output>250</output>

<gadget id="calculator">250 / 25</gadget>
<output>10</output>

<result>10</result>