IKMC 2025 - Grades 11-12 - Set 2 - Self-study Question 14

Question 14

The diagram shows quarter-circle OPQ of centre O and radius r, and triangle OPR. The two shaded regions have equal areas. What is OR?

Question illustration

$\pi r/2$
$3r/2$
$\pi r$
$2/\pi$
$\pi/(2r)$