Two cities A and B are 300 kilometers apart. Two cars leave from city A and city B respectively at the same time. The speed of the bus is 90 km/h, and the speed of the truck is 60 km/h. After how many hours did the two cars meet.
A、B两市相距300千米，两辆汽车分别同时从A市和B市相对开出，客车速度是90千米/时，货车速度是60千米/时．经过多少小时两车相遇．
<gadget id="calculator">90 + 60</gadget>
<output>150</output>

<gadget id="calculator">300 / 150</gadget>
<output>2</output>

<result>2</result>