Two hundred fence posts are to be placed into the ground in a straight line, 3m apart. The fence posts are stacked in a pile along this same line, 3m from the position of the first post to be put in. Maybell is going to put in the posts one at a time in order, and each post she puts in is farther away from the pile. Maybell can only carry one post at a time, and so she always walks back to the pile to get the next post. If Maybell starts at the pile, how many kilometers mush she walk to finish the job?