Car A travels 40 kilometers per hour, and car B travels 60 kilometers per hour. Two cars depart from places A and B at the same time and drive toward each other. At 3 o'clock after meeting, car A arrives at place B. Find the distance between A and B.
甲车每小时行40千米，乙车每小时行60千米．两车分别从A，B两地同时出发，相向而行，相遇后3时，甲车到达B地．求A，B两地的距离．
<gadget id="calculator">40 + 60</gadget>
<output>100</output>

<gadget id="calculator">3 / 60</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">40 * (1/20)</gadget>
<output>2</output>

<gadget id="calculator">100 * 2</gadget>
<output>200</output>

<result>200</result>