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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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## Warning triangle II

A square, a triangle and two equal angles. What is the angle α?

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Three semicircles and a circle all touching each other. The diameters of the two smallest semicircles are given. The large triangle connects three tangency points. What is the area of the green quadrilateral?

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## The strawberry ice cream

Two tangent circles and a triangle. The figure has reflection symmetry in the vertical diameter d, of which one ninth is above the horizontal chord. What fraction is pink?

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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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