The radii of the two concentric circles are 27 cm and 18 cm. The area (in cm2) of the closed figure bounded by the boundaries of the circle is:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 405π.
Area of the larger circle = π(27)2 = 729π cm2
Area of the smaller circle = π(18)2 = 324π cm2
Area of the closed figure = 729π - 324π = 405π cm2