Two trains A and B depart from Ningbo and Shanghai at the same time. Train A travels 60 kilometers per hour, and train B travels 55 kilometers per hour. After 4 hours of meeting, how many kilometers is the total length from Ningbo to Shanghai?
甲、乙两辆列车同时从宁波、上海相对开出，甲车每小时行60千米，乙车每小时行55千米，经过4小时相遇，宁波至上海全长多少千米？
<gadget id="calculator">60 + 55</gadget>
<output>115</output>

<gadget id="calculator">115 * 4</gadget>
<output>460</output>

<result>460</result>