A bus travels 65 kilometers per hour. It takes 12 hours for this bus to go back and forth between the two cities. How many kilometers are the distance between the two cities?
一辆客车每小时行驶65千米，这辆客车在两城间往返一次需要12小时，两城相距多少千米？
<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">65 * 6</gadget>
<output>390</output>

<result>390</result>