Cars A and B are traveling towards each other from places A and B at the same time. Car A travels 75 kilometers per hour, and Car B travels 66 kilometers per hour. After 4 hours, the two cars meet on the way. How many kilometers long?
甲、乙两车同时从A、B两地相向而行，甲车每小时行75千米，乙车每小时行66千米，经过4小时两车在途中相遇，A、B两地公路全长多少千米？
<gadget id="calculator">75 + 66</gadget>
<output>141</output>

<gadget id="calculator">141 * 4</gadget>
<output>564</output>

<result>564</result>