A triangle containing a semicircle and an equilateral triangle. What fraction is golden?
A semicircle is inscribed in a rectangle. What is the minimal covered fraction?
A circle containing three squares. What fraction is coloured?
A regular octagon containing a blue hexagon. All line segments have equal length. What fraction is blue?
An equilateral triangle with an altitude. Two of its sides form the radii of the circular sector. What fraction of the area is covered by the red circle?
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?
A square with four congruent equilateral triangles. What fraction is yellow?
A rectangle is split by two perpendicular lines. The four circles pass through vertices and intersection points. Their centres form a purple quadrilateral. What fraction of the large rectangle area does it cover?
Two squares, three circles and a common tangent. What fraction is coloured?
A semicircle is inscribed in a quarter circle. What is the minimal yellow fraction?