Henk Reuling

A square with two inscribed squares. What is the maximal proportion green : blue? mirangu.com/the-oppressed-mi…

Two equilateral triangles share a side midpoint. What is the angle α? mirangu.com/the-pendulum/

A square and a rectangle share two vertices. If the square has twice the area of the rectangle, what’s the angle α? mirangu.com/five-to-twelve/

A square containing a quarter circle and a red equilateral triangle. What’s the orange fraction? mirangu.com/the-orange-fract…

A regular hexagon, a square with its diagonals, an equilateral triangle and a circle. Prove that the hexagon and the circle are concentric. mirangu.com/the-pit/

Two circles and two tangents. What is the yellow fraction? mirangu.com/the-fried-egg/

Two perpendicular squares inside a circle. The circle centre is located on the side of one square. The line segment connecting two vertices has length a. What is the circle area? mirangu.com/squaring-the-cir…