Two cars depart from places A and B at the same time, drive toward each other, and meet after 4 o'clock. The speeds of the two cars are 64 km/h and 76 km/h respectively. How many kilometers are there between A and B?
两辆汽车分别从A、B两地同时出发，相向而行，4时后相遇．两辆汽车的速度分别是每时64千米和每时76千米．A、B两地相距多少千米？
<gadget id="calculator">64 + 76</gadget>
<output>140</output>

<gadget id="calculator">140 * 4</gadget>
<output>560</output>

<result>560</result>