Shortest distance between places

There are five farms lying near a narrow road. Find out a milk collection place where each farmer covers the shortest distance possible, if every farmer delivers milk once daily and the single farms lie at the milestones described by the following table?

Farm A 7.7

Farm B 22.5

Farm C 16.5

Farm D 10.2

Farm E 13.1

The question is part of a statistics h/work where things like standard deviation, variation, median and so on are to be calculated. But I don't know which, if, any of these are relevant to this question. Any help is appreciated.