An express train is 250 meters long and travels 500 meters per minute. How many minutes does it take for this express train to pass through a tunnel 850 meters long?
一列快车，车长250米，每分钟行500米．这列快车通过一个长850米的隧道，需要多少分钟．
<gadget id="calculator">850 + 250</gadget>
<output>1_100</output>

<gadget id="calculator">1_100 / 500</gadget>
<output>11/5 = around 2.2</output>

<result>11/5 = around 2.2</result>