Circumference and Area of Circles

Does this picture show the diameter or radius of a circle?

• Diameter
• Radius

What is the radius of this circle?

• 12
• 6
• 24

Find the circumference of the circle in the image.

• 31.4 units

• 62.8 units

• 314 units

• 20 units

The radius of the circle is 9 meters. What is the circle's circumference?

• 14.13 meters

• 28.26 meters

• 56.52 meters

• 18 meters

A cruise ship has a large, circular window. It has a diameter of 6 meters. What is the window's approximate circumference?

• 3 m 
• 9.42 m
• 12 m
• 18.84 m

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

• c = 15π
• C = 2π15
• c = 15/π
• c = 15/2π

Find the area of the circle. Use 3.14 for π.

• 803.84 cm²

• 25.12 cm²

• 50.24 cm²

• 200.96 cm²

What is the area of this circle?

• 50.27
• 78.23
• 98.12
• 201.06

A clock face has a diameter of 10 inches. What is the approximate area of the clock face in square inches?

• 314 in²
• 31.4 in²
• 7.85 in²
• 78.5 in²

Ms. Catall is using a compass to find her way out of the woods. The compass has a radius of 4 centimeters. What is the compass's area?

• 200.96 cm²

• 12.56 cm²

• 50.24 cm²

• 25.12 cm²