A passenger car and a truck travel opposite each other from A and B at the same time. It takes 10 hours for the bus to complete the journey, and 15 hours for the truck. When the two cars meet, they are exactly 25 kilometers away from the midpoint of AB. Find the distance between A and B.
客车和货车分别从A、B两地同时相对而行，客车行完全程需10小时，货车需15小时．两车相遇时，正好距AB两地中点25千米，求A、B两地的距离．
<gadget id="calculator">25 * 2</gadget>
<output>50</output>

<gadget id="calculator">3 + 2</gadget>
<output>5</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(3/5) - (2/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">50 / (1/5)</gadget>
<output>250</output>

<result>250</result>