The answer is .6 repeating.
The map is a flat schematic of some actual distance, on a map, the distance form point A to point B may well be 10 units say, however, in actuality, if you go and walk from point A to point B, you'd notice that, first off is not a straight line most of the time, and also it may have a slanted or sloped section, and the map is not including that slope or hill, whilst you do have to walk it.
so, adding all the twists and curves along the way and any bumps or slopes, is really not exactly 10 units from A to B.
