The distance between A and B is 60 km. Two cars depart from A to B at the same time, and A arrives at B 30 minutes earlier than B. When car A arrives at point B, car B is still 10 kilometers away from point B. How many hours did it take for car A to travel from point A to point B?
A、B两地相距60千米．两辆汽车同时从A地出发前往B地，甲车比乙车早30分钟到达B地．当甲车到达B地时，乙车离B地还有10千米．甲车从A地到B地共行了几小时？
<gadget id="calculator">10 / 0.5</gadget>
<output>20</output>

<gadget id="calculator">60 / 20</gadget>
<output>3</output>

<gadget id="calculator">3 - 0.5</gadget>
<output>2.5</output>

<result>2.5</result>