A passenger car and a truck depart from City A and City B respectively at the same time and drive toward each other. The bus travels 70 kilometers per hour, and the truck travels 60 kilometers per hour. The two cars meet after driving for 4 hours. How many kilometers are the distance between A and B?
客车和货车分别从甲城和乙城同时出发，相向而行，客车每小时行70千米，货车每小时行60千米．两车行驶4小时后相遇，甲、乙两城相距多少千米？
<gadget id="calculator">70 + 60</gadget>
<output>130</output>

<gadget id="calculator">130 * 4</gadget>
<output>520</output>

<result>520</result>