The distance between A and B is 500 kilometers. The two trains A and B have traveled for 4 hours and have not met yet. They are still 20 kilometers apart. It is known that the speed of A train is 65 kilometers per hour. Then the speed of B train is How many?
A、B两地相距500千米，甲、乙两辆火车行了4小时后仍未相遇，还相距20千米，已知甲火车的速度为65千米/时，那么乙火车的速度是多少？
<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>