A passenger car and a truck are traveling towards each other from A and B respectively. The passenger car travels 68 kilometers per hour, the truck travels 42 kilometers per hour, and the two vehicles meet after 4.5 hours. How many kilometers are there between A and B?
一辆客车和一辆货车分别从甲乙两地相向而行．客车每小时行68千米，货车每小时行42千米，经过4.5小时两车相遇．甲乙两地相距多少千米？
<gadget id="calculator">68 + 42</gadget>
<output>110</output>

<gadget id="calculator">110 * 4.5</gadget>
<output>495</output>

<result>495</result>