The circumference of a circle can be calculated using the formula C = 2πr, where C represents the circumference and r represents the radius of the circle.
In this case, the radius is 4. Plugging this value into the formula, we get:
C = 2π(4)
This simplifies to:
C = 8π
To give a numerical approximation, you can use the value of π (pi) which is approximately 3.14. Therefore, the circumference can also be calculated as:
C ≈ 8 × 3.14 = 25.12
So, the circumference of a circle with a radius of 4 is 8π or approximately 25.12 units.