From A to B, uphill roads account for (2/9), flat roads account for (4/9), and the rest are downhill roads. A car starts from place A, goes back and forth between places A and B, and travels a total of 25km downhill. How many kilometers is the distance between places A and B?
从甲地到乙地，上坡路占(2/9)，平坦路占(4/9)，其余是下坡路．一辆汽车从甲地出发，在甲乙两地间往返一趟，共行下坡路25km．求甲乙两地的路程是多少km？
<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">1 - (2/9) - (4/9)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) + (2/9)</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">25 / (5/9)</gadget>
<output>45</output>

<result>45</result>