I saw this video on the Mind Your Decisions youtube channel. The full video can be found here and the accompanying article can be found here. They are both kind of lengthy and don’t provide any hints to help you so I’ve put a short version of the answer and some clues below.
The problem is solvable by everyone but even the maths guru who made the video admits that he didn’t manage it at first.
Clue 1 – There is a complicated method of solving this but there is also a simple method.
Clue 2 – Amazon were very particular about the lengths and heights that they picked.
Clue 3 – Try drawing the diagram out to scale.
Clue 4 – Use a compass.
Given that the rope will hang symmetrically…
the rope is 80m long, so half the length of the rope is 40m.
The poles are 50m high and the rope needs to hang 10m from the bottom (50m – 10m = 40m).
So for a 40m rope to hang 10m from the ground of a 50m pole, it will need to hang straight down and then come straight back up so the distance between the pole is 0m!
The diagram is just there to throw you 🙂