Two trains, A and B, depart from two places 500 kilometers apart at the same time. After 4 hours, they do not meet and the distance is 40 kilometers. It is known that train A travels 65 kilometers per hour. How many kilometers per hour does train B travel?
甲乙两列火车同时从相距500千米的两地相对开出，4小时后没有相遇还相距40千米，已知甲车每小时行65千米，乙车每小时行多少千米？
<gadget id="calculator">500 - 40</gadget>
<output>460</output>

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

<gadget id="calculator">115 - 65</gadget>
<output>50</output>

<result>50</result>