The distance between A and B is 500 kilometers. Two cars drive from the two places at the same time. After driving for 5 hours, the two cars meet. The passenger car travels an average of 60 kilometers per hour, how many kilometers per hour does the truck travel on average?
甲乙两地相距500千米，两车同时从两地相对出，开出5小时后两车相遇．客车平均每小时行60千米，货车平均每小时行多少千米？
<gadget id="calculator">500 / 5</gadget>
<output>100</output>

<gadget id="calculator">100 - 60</gadget>
<output>40</output>

<result>40</result>