Don't worry, the question is correct!
Geometry
Level
3
How many points are there on the globe where by walking one mile south, one mile east and one mile north you reach the place where you started?
Assumptions-
Take the globe to be considerably large, like Earth.
Infinity
6400
1
2
0
540
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1 solution
The north pole is one such place.
However consider the points 1 + 2 π 1 away from the South Pole. Let any of those points be A and then go a mile south to a point B. When you go a mile east, you end up back at point B (you travelled once through every line of longitude). A mile north then brings you back to point A.
There are points still closer to the south pole such that going a mile east brings you through each line of longitude exactly twice, three times, or as many times as you want. Thus we have an infinite number of concentric rings of i n f i n i t e numbers of points, and we can start a mile north of any of them.