A car travels 144 kilometers per hour, which is twice the speed of a bus. It takes 1 hour and 30 minutes for a car to travel from City A to City B, how long does it take for a bus to travel from City A to City B?
一辆小汽车每小时行144千米，是大客车速度的2倍．小汽车从甲城到乙城要行1小时30分钟，大客车从甲城到乙城需多长时间．
<result>3</result>