Area and circumference both relate to the radius and diameter of a circle. Once you know one, you can find all of the others --It just takes a little math!
If a circle's diameter is 10, calculate its circumference and area?
Answer
circumference = Π×diameter
= 10 Π
radius = diameter÷2 = 10÷2 =5
area = Π(radius)² =Π(5)² = 25Π
A circle's area is 16Π. What is its circumference?
Answer
A = Π (radius)²
= 16Π radius² = 16 radius = 4
circumference = 2Π×radius =2Π×4 = 8Π
If a circle has a circumference of 26Π, what is its area?
Answer
circumference = 2Π(radius)
= 26Π 2×radius = 26 radius = 13
area = Π(radius)² =Π(13)² =169Π