A passenger car and a truck start from A and B at the same time and drive toward each other. The passenger car travels 80 kilometers per hour and the truck travels 65 kilometers per hour. The truck travels 51 kilometers before the bus starts. As a result, the two cars meet at the midpoint between places A and B. How many kilometers has the bus traveled?
一辆客车和一辆货车同时从甲、乙两地出发，相向而行．客车每小时行80千米，货车每小时行65千米．货车先行51千米后客车才出发，结果两车正好在甲乙两地的中点相遇，这时客车行了多少千米？
<gadget id="calculator">80 - 65</gadget>
<output>15</output>

<gadget id="calculator">51 / 15</gadget>
<output>17/5 = around 3.4</output>

<gadget id="calculator">80 * (17/5)</gadget>
<output>272</output>

<result>272</result>