A passenger car and a freight train leave from two stations A and B at the same time. The passenger car travels 60 kilometers per hour, and the freight car travels 50 kilometers per hour. After 4 hours, the two vehicles meet. How many kilometers are the distance between A and B?
客车和货车同时从甲、乙两站对开，客车每小时行驶60千米，货车每小时行驶50千米，经4小时两车相遇，甲、乙两站相距多少千米？
<gadget id="calculator">60 + 50</gadget>
<output>110</output>

<gadget id="calculator">110 * 4</gadget>
<output>440</output>

<result>440</result>