pole factory is 1,000 meters away from the intersection of the highway. Now the pole factory has 20 poles, all of which need to be transported and placed on the side of the road. The first pole is placed from the intersection, and one is placed every 100 meters in the future. One car A maximum of 3 poles can be transported at a time. How many kilometers does the car have to travel at least to return to the pole factory after transporting and releasing the poles?
一电杆厂距公路路口1000米，现在电杆厂有20根电杆，需全部运来放在公路边，并且从路口开始放第一根，以后每隔100米放一根，一辆车一次最多运3根，问这辆车运放完电杆后回到电杆厂最少要走多少千米？
<gadget id="calculator">28_000 / 1_000</gadget>
<output>28</output>

<result>28</result>