It takes 40 seconds for a train to pass through a 530-meter tunnel, and 30 seconds to pass through a 380-meter bridge at the same speed. How long is the train?
一列车通过530米的隧道要40秒钟，以同样的速度通过380米的大桥要用30秒钟，这列火车车长多少米．
<gadget id="calculator">530 - 380</gadget>
<output>150</output>

<gadget id="calculator">40 - 30</gadget>
<output>10</output>

<gadget id="calculator">150 / 10</gadget>
<output>15</output>

<gadget id="calculator">15 * 40</gadget>
<output>600</output>

<gadget id="calculator">600 - 530</gadget>
<output>70</output>

<result>70</result>