A car transports the poles to the line, and loads them from the starting point, pulling 4 poles each time. The distance between every two poles on the line is 50 meters, and it is transported twice. It takes 3 hours to return to the original place after loading and unloading. It takes 30 minutes to load a car and 5 minutes to unload a utility pole. The average speed of the car is 30 kilometers per hour. What is the distance in kilometers?
一辆汽车往线路上运送电线杆，从出发地装车，每次拉4根，线路上每两根电线杆间的距离为50米，共运了两次．装卸结束后返回原地共用了3小时，其中装一次车用30分钟，卸一根电线杆用5分钟，汽车运行时的平均速度是每小时30千米，则从出发点到第一根电线杆的距离是多少千米？
<gadget id="calculator">4 / 3</gadget>
<output>4/3 = around 1.333333</output>

<gadget id="calculator">30 * (4/3)</gadget>
<output>40</output>

<gadget id="calculator">40 - 0.3 - 0.3 - 0.4</gadget>
<output>39</output>

<gadget id="calculator">39 / 4</gadget>
<output>39/4 = around 9.75</output>

<result>39/4 = around 9.75</result>