A highway is 486 kilometers long. A passenger car can complete the journey in 4.5 hours, and a truck can complete the journey in 5.4 hours. How much slower is the speed of the truck than the passenger car?
一段高速公路长486千米，一辆客车4.5小时可行完全程，一辆货车5.4小时可行完全程，货车的速度比客车的速度慢多少？
<gadget id="calculator">486 / 4.5</gadget>
<output>108</output>

<gadget id="calculator">486 / 5.4</gadget>
<output>90</output>

<gadget id="calculator">108 - 90</gadget>
<output>18</output>

<result>18</result>