A square divided by three line segments. What’s the proportion yellow : purple?
Tag: area
Égalité
A square with its diagonal and a circle. If red is equal to blue, what’s the angle α?
Spiegel im Spiegel
A triangle with an inscribed triangle. What fraction of the former does the latter cover in terms of lengths a, b, c, d, e and f?
The green necktie
A square with several line segments. What fraction is green?
House of Orange
A right triangle with a red and yellow square attached. Two circular arcs centered in the triangle vertices. What is the area of the orange rectangle in terms of red and yellow?
Out of proportion
An equilateral triangle containing a parallelogram, another equilateral triangle and a circular arc that is tangent in its base vertices. What is the proportion pink : blue?
Head above water
A unit square with an extended side immersed in another square. What is the area of the red triangle?
The framing effect
Four squares, three of which are coloured. What’s the area of the blue one?
Projection bias
Two regular pentagons are placed side by side. What’s the proportion blue : green?
Take five origami
Divide a rectangular piece of paper in five pieces of equal area. You only have a pair of scissors at your disposal, but you are allowed to make straight folds to guide you.