The railway between A and B is 640 kilometers long. A train departs from A to B at 8 am and arrives at 4 pm. How many kilometers per hour does the train travel on average?
甲乙两城铁路长640千米，一列火车于上午8时从甲城开往乙城，下午4时到达．这列火车平均每小时行多少千米？
<gadget id="calculator">640 / 8</gadget>
<output>80</output>

<result>80</result>