Radius, Diameter, Circumference, and Pi

12 inches in this circle represents its

• radius

• diameter

14cm in the circle represents its

• radius

• diameter

What is the length of the diameter of the circle?

What is the length of the radius of the circle?

What does "circumference" mean?

• Space a circle takes up
• Distance around a circle
• Line from one side of a circle to another
• Line from center of circle to side

What is the formula for finding the circumference of a circle?

• C = r²

• C = rd

• A = π·r²

• C = π·d

Find the circumference of the circle

What is the approximate circumference? (use 3.14 for pi)

Find the circumference of the circle

Find the circumference of the circle.