The formula for the circumference c of a circle is given by:
c = 2πr
Where:
- c is the circumference of the circle.
- r is the radius of the circle.
- π (pi) is a constant approximately equal to 3.14159.
This formula is derived from the relationship of the radius and the entire perimeter of the circle. Essentially, if you take the radius and multiply it by 2, you get the diameter of the circle. Since the circumference is the distance around the circle, multiplying the diameter by π gives you the circumference. So, in simple terms, the circumference is just the radius times 2 and then multiplied by pi.