On the expressway, a passenger car is driving forward at a speed of 51 km/h. At a place 48 km away from the passenger car, a car is catching up at a speed of 67 km/h. A few hours later Can a car catch up to a passenger car?
在高速公路上，一辆客运车正以51千米/时的速度向前行驶，在离客运车48千米的地方，一辆轿车正以67千米/时的速度赶上来，几小时后轿车能追上客运车？
<gadget id="calculator">48 / 12</gadget>
<output>4</output>

<result>4</result>