+349 Two regular pentagons and a regular decagon, all with the same side length, can completely surround a point.
An equilateral triangle, a regular decagon, and a regular n-gon, all with the same side length, also completely surround a point. Find n.
+111 The sum of interior angles at a point that is completely surrounded by polygons must be 360 degrees.
The interior angle of a regular polygon with n sides is calculated as (180(n-2))/n.
