passenger car is driving from A to B, and a truck is driving from B to A at the same time. The truck passes the midpoint 28 kilometers and meets the bus. It is known that the speed ratio of passenger cars and trucks is 5:7, how many kilometers are there between A and B?
一辆客车从甲地开往乙地，同时一辆货车从乙地开往甲地，货车驶过中点28千米与客车相遇．已知客车与货车的速度比是5：7，甲、乙两地相距多少千米？
<gadget id="calculator">5 + 7</gadget>
<output>12</output>

<gadget id="calculator">7 / 12</gadget>
<output>7/12 = around 0.583333</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(7/12) - (1/2)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">28 / (1/12)</gadget>
<output>336</output>

<result>336</result>