It takes 30 seconds for a train to pass a 480-meter-long bridge; it takes 36 seconds to pass a 600-meter-long bridge at the same speed. What is the length of the train in meters? (Solve with ratio)
一列火车经过一座长480米的桥用时30秒；用同样的速度经过长600米的桥，用了36秒．求火车的长度是多少米？(用比例解)
<gadget id="calculator">600 / 36</gadget>
<output>50/3 = around 16.666667</output>

<gadget id="calculator">480 / 30</gadget>
<output>16</output>

<gadget id="calculator">(50/3) - 16</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">1 / 36</gadget>
<output>1/36 = around 0.027778</output>

<gadget id="calculator">(1/30) - (1/36)</gadget>
<output>1/180 = around 0.005556</output>

<gadget id="calculator">(2/3) / (1/180)</gadget>
<output>120</output>

<result>120</result>