We have been given that length of the trail is 20 miles and there are markers at each mile.
Initially, the person walks from 0-mile mark and stops at 4-mile mark.
We need to know figure out the mile mark that is equidistant from the starting point as well as from the stopping point.
That is, we need to figure out the mile mark that is equidistant from 0-mile mark and 4-mile mark.
Considering that walking trail is round, the 0-mile mark as well as 20-mile mark will be the same point. Therefore, we need to basically, find the mid point of 4 and 20. It would be [tex]\frac{4+20}{2} =\frac{24}{2} =12[/tex].
Therefore, 12-mile mark is equidistant from stopping point and 0.
