Semicircle Stack
What is the total area enclosed by the three semicicles?
Age
14 to 16
Challenge level
Problem
Image
The diagram shows three semicircles, each of radius one.
What is the size of the total area shaded?
Student Solutions
Image
(all of radius $1$).
Hence the total area is that of the rectangle
plus a circle of radius $1$ which equals $2 + \pi$