A Geometer's Fallacy
Geometry
Level
1
Which of the following figures has the greatest area shaded in red?
Assumptions:
- A, B, C are identical equilateral triangles. The circles of A are all congruent to each other, as are the circles of C.
- The red components are circles tangent to one another and to the triangle.
Note: If you get it wrong, don't worry! An Italian mathematician named Malfatti also got it wrong in the \(19^\text{th}\) century.
by
Andrei Li