Circumference and Area

Find the circumference of the circle

• 21.98

• 153.86

• 43.96

• 615.44

What is the area of the circle? (Best Choice)

• 3π or about 9.42 in²

• 6π or about 18.84 in²

• 12π or about 37.68 in²

• 36π or about 113.04 in² 

Is the red line a radius or diameter of the circle?

• Radius

• Diameter

What is the radius of this circle?

• 18

• 36

• 9

• 6

Match the following definitions to the terms:

• square units (units²)

• Area of a circle

• The distance around a circle

• Units of circumference

• feet, cm, inches

• Units of area

• How much space a circle takes up

• Circumference of a circle

• 25.12 inches

• 12.56 inches

• 50.24 inches

• 31.4 inches

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

• c = 15π

• c = 2π15

• c = π(15²)

• c = π(7.5²)

A Circle has a diameter of 18 meters. What is the circumference of the circle? (Best Choice)

• 9π or about 28.26 m

• 18π or about 56.52 m

• 81π or about 254.34m

• 324π or about 1017.36 m

The radius is 8 inches.  What is the circumference?

• 50.24 inches

• 25.12 inches

• 12.56 inches

• 200.96 inches

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