Categories
Intermediate

The balancing act

A square with two perpendicular lines. What is the minimal blue fraction?

Categories
Intermediate

Softening the edges

A quarter circle contains a semicircle and a square. What fraction of the area is purple?

Categories
Intermediate

The honeycomb

Two regular hexagons inscribed in a square. If the hexagons have side length a and b, what is the square’s side length?

Categories
Intermediate

The folded napkin

A square sheet of paper is folded symmetrically from a corner. If the fold length is 4, what is the area of the triangle formed by the other three corners?

Categories
Intermediate

Together we stand

Two squares sharing a vertex. What’s the angle α?

Categories
Intermediate

The pleasure dome

A semicircle with three squares. The areas of the smaller squares are given. What is the area of the biggest one?

Categories
Intermediate

Triple dice

An equilateral triangle with three congruent squares. What’s the angle α?

Categories
Beginner

The wall

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

Categories
Advanced

The satellite

A circle containing three squares. What fraction is coloured?

Categories
Intermediate

The Lion King II

A regular hexagon and three squares. What is the proportion yellow : brown?