The distance between A and B is 630 kilometers. The train departs from A at 13:40 and arrives at B at 20:40 on the same day. How many kilometers per hour does the train travel on average?
甲乙两地相距630千米，火车从甲地13：40出发，当日20：40到达乙地．这列火车平均每小时行多少千米？
<gadget id="calculator">630 / 7</gadget>
<output>90</output>

<result>90</result>