A train is 150 meters long and travels 20 meters per second. How long does it take for the entire train to pass through a 250-meter-long bridge?
一列火车长150米，每秒行20米，全车通过一座长250米的大桥，需要多长时间？
<gadget id="calculator">150 + 250</gadget>
<output>400</output>

<gadget id="calculator">400 / 20</gadget>
<output>20</output>

<result>20</result>