Let a "fold-point" of a triangle be defined as a place on the triangle to which the three corners can all be folded simultaneously, such that no folds overlap. What are the shape and area of the region surrounding all fold-points for: If you find any extensions to this problem, let me know. For example: Source: Original, based on a puzzle in rec.puzzles. Used as Ken's Puzzle of the Day 4/26/94.
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