It takes 19.5 hours to travel from city A to city B by train in early 1998. In 1998, the speed of the train increased by 30% for the first time, in 1999, for the second time, by 25%, and in 2000, for the third time, the speed increased by 20%. After these three speed increases, how long does it take to travel from city A to city B by train?
乘火车从甲城到乙城，1998年初需要19.5小时，1998年火车第一次提速30%，1999年第二次提速25%，2000年第三次提速20%．经过这三次提速后，甲城到乙城乘火车只需多少小时．
<result>10</result>