Two trains, A and B, depart from two places 500 kilometers apart at the same time. They do not meet each other after 4 hours and are still 20 kilometers apart. 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20千米，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 - 20</gadget>
<output>480</output>

<gadget id="calculator">480 / 4</gadget>
<output>120</output>

<gadget id="calculator">120 - 65</gadget>
<output>55</output>

<result>55</result>