Question: how to calculate the diameter and radius of a circle?
Answer: Take the circumference of a circle and divide it by Pi. For example, if the circumference is 12.56, you would divide 12.56 by 3.14159 to get 4, which is the diameter of the circle. Use the diameter to find the radius by dividing the diameter by 2. For example, if the diameter is 4, the radius would be 2.