it depends on what the radius is if they give you one
The approximate radius is five (5) inches.
Divide the circumference (38") by Pi (about 3.1416) to get the diameter in inches.
Most scientific calculators have a button for pi. So to find the circumference of a circle multiply pi by the diameter. If there is no pi button you can approximate pi as 3.14.
A track 7m wide consists of two concentric circles. The circumference of the inner circle is 440m. Find, 1) the radius of the outer circle 2) the circumference of the outer circle.
The formula; 2 * Pi * Radius = circumference Will calculate the circumference of a circle.
If you want an approximate answer, you can measure it with string. If you want an exact answer and know the radius, multiply by 2*pi to find the circumference.
The circumference is the diameter times pi. It will always be approximate because of the nature of pi.
find the radius of a circle with circumference of 42.1
The circumference of a circle is the length of the circle's perimeter.
If you know the circumference of a circle, you can find the radius by dividing the circumference by the value of Pi (3.14159...)
Diameter of a circle = circumference/pi
circumference of a circle = 2piradiuis or diameter*pi