Categories
Advanced

The birdwatcher

Two congruent circles and a right triangle inside a semicircle. What fraction is blue?

Categories
Beginner

The hammock

A square inscribed in a triangle. Two areas are given. What is the square’s area?

Categories
Intermediate

The cleaver

Four squares, a rectangle and a circle. What is the proportion brown : grey?

Categories
Beginner

The green field

A square is divided in two quadrilaterals of given area. What fraction of the square’s perimeter is red?

Categories
Intermediate

Ice cube

A rectangle and a square. What is the proportion purple : blue?

Categories
Intermediate

The hourglass

A rectangle with two crossing line segments. What’s the minimal shaded fraction?

Categories
Beginner

Papillon

Four quarter circles of radius 1, each containing a square. What is the blue area?

Categories
Intermediate

Below the tree line

A triangle is split in two. What is the area of the green quadrilateral in terms of lengths a and b?

Categories
Intermediate

The ramp

A right triangle is split in two. What is the maximum yellow fraction?

Categories
Beginner

The headphones

A unit square, a semicircle, a right triangle and an isosceles triangle. What is the total purple area?