The distance between A and B is 120 kilometers. A passenger car and a truck drive from A to B at the same time. As a result, the passenger car arrives at B half an hour earlier than the truck. It is known that the speed ratio of passenger and freight vehicles is 6:5. Calculate What is the speed of the truck in kilometers per hour?
甲乙两地相距120千米，一辆客车和一辆货车同时从甲地驶往乙地，结果客车比货车早半小时到达乙地，已知客、货两车的速度比为6：5，求货车的速度是每小时多少千米？
<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">1 - (5/6)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">0.5 / (1/6)</gadget>
<output>3</output>

<gadget id="calculator">120 / 3</gadget>
<output>40</output>

<result>40</result>