Exploring Circumference and Area of Circles

What does the circumference of a circle measure?

• The area inside the circle

• The diameter of the circle

• The distance around the circle

• The radius of the circle

Which formula represents the circumference of a circle using the diameter?

• C = 2πr

• C = πr

• C = πd

• C = r/π

How is the diameter related to the radius of a circle?

• Diameter is half the radius

• Radius and diameter are equal

• Radius is twice the diameter

• Diameter is twice the radius

For a circle with a radius of 8 miles, what is the formula to calculate its circumference?

• C = 2π × 16

• C = π × 8

• C = 2π × 8

• C = π × 16

If the radius of a circle is 8.3 yards, what is its approximate circumference?

• 104.4 yards

• 16.6 yards

• 26.1 yards

• 52.2 yards

What is the circumference of a circle with a radius of 4.2 yards?

• 8.4 yards

• 26.4 yards

• 13.2 yards

• 52.8 yards

How do you calculate the circumference if only the radius is given?

• C = πr

• C = πd

• C = 2πr

• C = r/2π

What is the rounded circumference of a circle with a radius of 9.5 inches?

• 59.7 inches

• 29.85 inches

• 39.8 inches

• 19 inches

For a circle with a radius of 11.1 feet, what is its approximate circumference?

• 34.85 feet

• 22.2 feet

• 44.4 feet

• 69.7 feet

What is the circumference of a circle with a radius of 9.3 inches?

• 58.4 inches

• 37.2 inches

• 29.15 inches

• 18.6 inches