passenger car and a truck leave from places A and B facing each other. The passenger car travels 68 kilometers per hour, and the freight car travels 3 kilometers longer than the passenger car per hour. The two cars leave opposite places at the same time and meet each other in 3 hours. How many kilometers are there between A and B?
一辆客车和一辆货车从甲、乙两地相对开出，客车每小时行驶68千米，货车每小时比客车多行3千米，两车同时从两地相对开出，3小时相遇，甲、乙两地相距多少千米？
<gadget id="calculator">68 + 3</gadget>
<output>71</output>

<gadget id="calculator">68 + 71</gadget>
<output>139</output>

<gadget id="calculator">139 * 3</gadget>
<output>417</output>

<result>417</result>