The distance between A and B is 660 kilometers. A bus and a truck leave from A and B respectively. The bus travels 60 kilometers per hour, and the truck travels 50 kilometers per hour. The two vehicles are on the way for several hours. meet?
A、B两地相距660千米，一辆客车和一辆货车分别从A、B两地相对开出，客车每小时行60千米，货车每小时行50千米，两车几小时在途中相遇？
<gadget id="calculator">60 + 50</gadget>
<output>110</output>

<gadget id="calculator">660 / 110</gadget>
<output>6</output>

<result>6</result>