A sector with radius 12 cm has area 132 cm². Find the central angle.
105°
110°
115°
120°
Correct answer: 105°
Solution
For a sector, \(\text{Area} = \frac{\theta}{360}\pi r^2\). With \(r=12\), we get \(132 = \frac{\theta}{360}\pi(144)\). Using \(\pi=\frac{22}{7}\), this gives \(\theta \approx 105^\circ\).