Circles and Circum

What is the circumference of a circle with a radius of 21 cm?

• 131.9 cm

• 121.9 cm

• 111.9 cm

• 141.9 cm

Which equation would you use to find circumference?

• πr²

• πd

• 2r

• ½d

What is the diameter of the circle?

• 3

• 6

• 9

• 12

What is the radius of the circle?

• 2cm

• 5cm

• 10cm

• 20cm

What is the circumference of the circle? Round to the nearest centimeter.

• 16 cm²

• 61 cm²

• 16 ft²

• 61 ft²

Which of the following best describes the value of pi?

• The relationship between the circumference and diameter

• The relationship between the circumference and radius

• The relationship between the diameter and radius

• The relationship between the circumference and center

What is the circumference?

• 12π cm

• 24π cm

• 6π m

• 3π m

Steven purchases a bowl. The diameter of the
bowl is 14 cm. What is the circumference of the 
bowl?

• 28 cm

• 43.96 cm

• 87.96 cm

• 7 cm

A DVD has a diameter of 15 millimeters. Which equation would help you determine the circumference?

• c = 15π

• C = 2π15

• c = 15 ÷ π

• c = 15 π

What is circumference?

• The distance around a circle.

• The space inside the circle.

• A line from side to side passing through the center.

• A line from the center to the side.