Two congruent rectangles and squares. Proof that the four points are on one circle.
Category: Beginner
Categories
The pentagon push
Two regular pentagons share a vertex. What’s the angle α?
Categories
The blue pill
A regular octagon containing a blue hexagon. All line segments have equal length. What fraction is blue?
Categories
The dangling square
Four squares and five shared vertices. If the orange area is 4, what is the green area?
Categories
The yellow sailboat
A square, two equilateral triangles and an extended side. What is the proportion yellow : blue?
Categories
Mondriaan II
A square contains three squares (black sides), one of which has an extended side (blue). What is the proportion yellow : blue?
Categories
Seventies tipi II
A triangle containing two tangent semicircles. What’s the proportion α : β?
Categories
The inner sanctum
A square with four congruent equilateral triangles. What fraction is yellow?
Categories
Out of the box
Two squares and two given areas. What’s the total area?
Categories
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?