There are 240 kilometers between A and B. It takes 4 hours for a train to travel halfway from A to B. How many kilometers does the train travel per minute?
A、B两地有240千米，一列火车从A地到B地，行到一半路程时用了4小时，这列火车每分钟行多少千米．
<gadget id="calculator">240 / 2 / 240</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>