Two semicircles inside a rectangle. What is the proportion of the red to the green area?
Month: December 2020
Domino day
Three congruent rectangles consisting of two squares each are placed as shown. What is the blue area?
The carambole
Three touching congruent circles inscribed in an equilateral triangle. A small equilateral triangle inscribed in the centre space. What fraction is blue?
The eye of the beholder
A square and two equilateral triangles inside and touching a circle. What’s the angle α?
The star of Bethlehem
Two concentric equilateral triangles with parallel sides. What fraction is orange?
The christmas tree
A triangle, a median and another cevian. What is the proportion of the two areas?
The bowtie
A square and two congruent isosceles triangles with variable top angle. What is the maximum fraction shaded?
The inner triangle
A triangle and two medians. What fraction is shaded?
The ace of diamonds
Four congruent right triangles form a rectangle. What fraction is red?
The tip of the iceberg
A triangle with a 45° angle is placed inside a square as shown. What’s the area proportion of parts A and B?