What is the area of a 12 inch and a 9 inch circle?
The area of a circle is calculated using the formula A = πr^2, where r is the radius of the circle. For a 12-inch circle, the radius is half of the diameter, so the radius is 6 inches. Therefore, the area of the 12-inch circle is A = π(6)^2 = 36π square inches. Similarly, for a 9-inch circle, the radius is 4.5 inches, so the area of the 9-inch circle is A = π(4.5)^2 = 20.25π square inches.