A train is 180 meters long, travels 20 meters per second, and has to pass a 620-meter-long bridge, how many seconds does it take for the whole train to pass?
一列火车长180米，每秒行20米，要经过一座长620米的桥，求全车通过需要多少秒？
<gadget id="calculator">180 + 620</gadget>
<output>800</output>

<gadget id="calculator">800 / 20</gadget>
<output>40</output>

<result>40</result>