The distance from Hangzhou to Huangshan is 240 kilometers. The speed of a train is 120 km/h and the speed of a car is 80 km/h. If the train and the bus depart from Hangzhou at the same time, how many hours will the train arrive at Huangshan earlier than the bus?
杭州到黄山相距240千米．一列火车的速度是120千米/时，一辆汽车的速度是80千米/时．如果火车和汽车同时从杭州出发，那么火车比汽车到达黄山的时间早多少小时．
<gadget id="calculator">240 / 80</gadget>
<output>3</output>

<gadget id="calculator">240 / 120</gadget>
<output>2</output>

<gadget id="calculator">3 - 2</gadget>
<output>1</output>

<result>1</result>