The length of the slow train is 142 meters, and its speed is 17 meters per second. The length of the fast train is 173 meters, and its speed is 22 meters per second. The slow train is driving ahead. How long does it take for the fast train to overtake the slow train from behind?
慢车的车身长是142米，车速是每秒17米，快车车身长是173米，车速是每秒22米，慢车在前面行驶，快车从后面追上到完全超过慢车需要多少时间？
<gadget id="calculator">142 + 173</gadget>
<output>315</output>

<gadget id="calculator">22 - 17</gadget>
<output>5</output>

<gadget id="calculator">315 / 5</gadget>
<output>63</output>

<result>63</result>