Area of a circle = pi times radius squared
Area = pi * radius * radius radius = diameter / 2 radius = 16/2 = 8 Area = 64 * pi Area 201.062 inches2
1 inch
2 inch radius = 12 9/16" circumference & an area of 12.56637 sq. inches.
Radius is 3 times as large so area is 3*3 = 9 times as large.
Area of a circle = pi times radius squared
1/2 inch
Area = pi * radius * radius radius = diameter / 2 radius = 16/2 = 8 Area = 64 * pi Area 201.062 inches2
In a circle, Area = pi times radius squared: A = (pi)(r^2) Since the diameter equals 2 inches, the radius is one inch: A = (pi)(1^2) A = pi = 3.14 inches squared
1 inch
2 inch radius = 12 9/16" circumference & an area of 12.56637 sq. inches.
If you are talking about 9 and 12 inch diameter, then divide both by 2 to get the radius. The area of a circle is pi (3.1415 is good for most calculations) multiplied by the square of the radius. So for the 12 inch circle, the radius is 6. The square of the radius is 36, and multiplying this by pi gives approximately 113.1 square inches. Now the 9 inch circle has a radius of 9/2 or 4.5. Squaring this we get 20.25, which multiplied by pi is approximately 63.6 square inches. If 9 and 12 were already the radius in the problem, just don't divide by 2 since you already have the radius.
Radius is 3 times as large so area is 3*3 = 9 times as large.
If that's the radius, use the standard formula for the area of a circle. If it's the diameter, divide it by 2 first, to get the radius.
The diameter of a 28-square inch circle is: 5.971 inches.
2 inches. the radius is half of the diameter
Radius of the circle: 3.65/2 = 1.825 inches