It takes 4 minutes for a train to cross a 2.7-kilometer long bridge from the front of the train to the end of the bridge. It is known that the speed of the train is 0.8 kilometers per minute. How long is this train?
一列火车通过一座长2.7千米的大桥，从车头上桥到车尾离桥共需4分．已知列车的速度是每分0.8千米．这列火车长多少米？
<gadget id="calculator">0.8 * 4</gadget>
<output>3.2</output>

<gadget id="calculator">3.2 - 2.7</gadget>
<output>0.5</output>

<gadget id="calculator">0.5 * 1_000</gadget>
<output>500</output>

<result>500</result>