A train of trucks and a train of passenger cars are traveling in the same direction. Since the truck has an urgent task, it begins to catch up with the passenger cars. Xiao Ming walked forward in the passenger car along the direction of the passenger car, and Xiao Ming found that the truck passed him in 140 seconds. It is known that Xiaoming’s walking speed in the bus is 1 meter per second, the speed of the bus is 20 meters per second, the length of the bus is 350 meters, and the length of the truck is 280 meters. Find the time it takes for the truck to completely overtake the passenger car from catching up with the passenger car.
一列货车和一列客车同向行驶，由于货车有紧急任务，因此开始赶超客车．小明在客车内沿着客车前进的方向向前走，小明发现货车用140秒就超过了他．已知小明在客车内行走的速度为每秒l米，客车的速度为每秒20米，客车长350米，货车长280米．求货车从追上客车到完全超过客车所需要的时间．
<gadget id="calculator">350 + 280</gadget>
<output>630</output>

<gadget id="calculator">280 / 140</gadget>
<output>2</output>

<gadget id="calculator">20 + 1 + 2</gadget>
<output>23</output>

<gadget id="calculator">23 - 20</gadget>
<output>3</output>

<gadget id="calculator">630 / 3</gadget>
<output>210</output>

<result>210</result>