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Permanent link to this puzzle: mscroggs.co.uk/puzzles/59

Four congruent triangles are drawn in a square.

The total area which the triangles overlap (red) is equal to the area
they don't cover (blue). What proportion of the area of the large square
does each (purple) triangle take up?

If you enjoyed this puzzle, check out Sunday Afternoon Maths LXII,

puzzles about probability, or a random puzzle.

puzzles about probability, or a random puzzle.