Two cars A and B are driving towards each other at the same time from two places 570 km apart. Car A travels 60 kilometers per hour. Due to a breakdown of the car, it takes 0.5 hours to repair the car; Car B travels 90 kilometers per hour. How many hours later did the two cars meet on the way?
甲、乙两辆汽车同时从相距570千米的两地相对而行．甲车每小时行60千米，由于汽车发生故障，修车用去0.5小时；乙车每小时行90千米．经过几小时后两车在途中相遇？
<gadget id="calculator">90 * 0.5</gadget>
<output>45</output>

<gadget id="calculator">570 - 45</gadget>
<output>525</output>

<gadget id="calculator">60 + 90</gadget>
<output>150</output>

<gadget id="calculator">525 / 150</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">(7/2) + 0.5</gadget>
<output>4</output>

<result>4</result>