truck and a bus drive from city A to city B at the same time. The truck travels 40 kilometers per hour, and the bus travels 60 kilometers per hour. The bus stops for two hours, but it still arrives 30 minutes earlier than the truck. How many miles is the distance between A and B?
货车和客车同时从甲城开往乙城．货车每小时行40千米，客车每小时行60千米，客车在中途停留两小时，但仍比货车早到30分．甲、乙两城相距多少千米．
<gadget id="calculator">2 + 0.5</gadget>
<output>2.5</output>

<gadget id="calculator">40 * 2.5</gadget>
<output>100</output>

<gadget id="calculator">60 - 40</gadget>
<output>20</output>

<gadget id="calculator">100 / 20</gadget>
<output>5</output>

<gadget id="calculator">60 * 5</gadget>
<output>300</output>

<result>300</result>