man is standing by the railway, and after hearing the siren of an oncoming train, the train passes in front of him in 81 seconds, and the train passes in front of him completely in 9 seconds. It is known that when the train whistles, it is 1360 meters away from him (the track is straight), and the speed of sound is 340 meters per second. Find the length of the train.
一个人站在铁道旁，听见迎面来的火车汽笛声后，再过81秒钟火车经过他面前，再过9秒钟火车完全经过他面前．已知火车鸣笛时离他1360米(轨道是笔直的)，声速是每秒钟340米，求火车的车长．
<gadget id="calculator">1_360 / 340</gadget>
<output>4</output>

<gadget id="calculator">81 + 4</gadget>
<output>85</output>

<gadget id="calculator">1_360 / 85</gadget>
<output>16</output>

<gadget id="calculator">16 * 9</gadget>
<output>144</output>

<result>144</result>