A circular plate having a radius of 10 cm and is surrounded by a decorative rim that is 2 cm wide. What is the area of the rim?
Show answer & explanation
Correct answer: A
Explanation
Inside radius = 10 cm
Rim width = 2 cm ⇒ Outside radius = 12 cm
Rim area = Area of larger circle − Area of smaller circle
= π(12² − 10²)
= π(144 − 100)
= 44π
≈ 44 × 3.14 = 138.23 square cm