The sector of a circle has radius of 21 cm and central angle 135o. Find its perimeter?
Q1. The sector of a circle has radius of 21 cm and central angle 135o. Find its perimeter?
Answer: 91.5 cm
Explanation: Arc length = (135/360) × 2π × 21 = 49.5 cm; perimeter = 49.5 + 2×21 = 91.5 cm.