CSEC Mathematics · January 2013 · Paper 1 · Question Q37

AOB is a sector of a circle such that angle AOB = 72^\circ and OB is r units long. The area of AOB is

1. (A)\frac{1}{5}\pi r
2. (B)\frac{2}{5}\pi r
3. (C)\frac{1}{5}\pi r^2
4. (D)\frac{2}{5}\pi r^2

This question uses a figure or table from the paper — you'll see it when you practise.