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The wall

Two congruent rectangles and squares. Proof that the four points are on one circle.

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The pentagon push

Two regular pentagons share a vertex. What’s the angle α?

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The blue pill

A regular octagon containing a blue hexagon. All line segments have equal length. What fraction is blue?

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The dangling square

Four squares and five shared vertices. If the orange area is 4, what is the green area?

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The yellow sailboat

A square, two equilateral triangles and an extended side. What is the proportion yellow : blue?

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Mondriaan II

A square contains three squares (black sides), one of which has an extended side (blue). What is the proportion yellow : blue?

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Seventies tipi II

A triangle containing two tangent semicircles. What’s the proportion α : β?

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The inner sanctum

A square with four congruent equilateral triangles. What fraction is yellow?

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Out of the box

Two squares and two given areas. What’s the total area?

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Mount Fuji

An equilateral triangle inscribed in a circle is divided by a diameter parallel to one of it’s sides. What is the proportion light : dark blue?