Categories
Beginner

The dirty thirties

A triangle containing a semicircle and a circular sector centred in the right vertex. What is blue : green?

Categories
Intermediate

Scratching the surface

Three tangent semicircles and two coloured triangles. What’s the proportion yellow : green?

Categories
Beginner

Family ties

Two regular pentagons share a vertex. What is the proportion red : green?

Categories
Beginner

Longing for spring

Four semicircles and three line segments. What’s the proportion yellow : orange?

Categories
Intermediate

A light packing

A triangle containing two congruent squares. Each square has 1/3 the perimeter and 1/6 the area of the triangle. What’s the triangle side length proportion a : b : c?

Categories
Intermediate

The seesaw

A regular hexagon with three diagonals and two line segments at right angles. What is the proportion green : yellow : blue : orange?

Categories
Intermediate

The Zamani suggestion

Two regular hexagons share a vertex. What’s the area proportion red : yellow hexagon?

Categories
Intermediate

Pushing the boundary

Two equilateral triangles are placed side by side. What’s the proportion green : red?

Categories
Advanced

Square one

Three squares share a vertex. Two line segments pass through side midpoints. Prove that a : b = c : d.

Categories
Intermediate

Letting go

Two squares share a vertex. Three other vertices are collinear. What is the area proportion of the blue to the red square?