A passenger car travels from city A to city B in 4.5 hours, 80 kilometers per hour; a truck can travel from city B to city A in 6 hours, how many kilometers per hour does the truck travel?
一辆客车4.5小时从甲城到乙城，每小时80千米；一辆货车6小时可以从乙城到甲城，货车每小时行多少千米？
<gadget id="calculator">4.5 / 6</gadget>
<output>0.75</output>

<gadget id="calculator">80 * 0.75</gadget>
<output>60</output>

<result>60</result>