Circumference, Radius, and Diameter

A circular swimming pool is 21 feet in diameter.
How many feet around is the pool?

• 10.5 ft

• 42 ft

• 65.94 ft

• 131.95 ft

Randy’s circular garden has a radius of 1.5 feet. He wants to enclose the garden edging that costs $0.75 per foot. About how much will the edging cost? 

• $8.00

• $7.00

• $3.50

• $0.50

The homeowners association wants to enclose the playground in a fence. How much fencing will they need to purchase? Is this question finding the area or the circumference?

• area

• circumference

• neither

Name the part of the circle pointed by the arrow.

• Radius

• Diameter

• Circumference

• Arc

Find the diameter of a circle if its radius is 7.5 meters. (Type the answer including the units)

Find the diameter of a circle if its radius is 8.42 inches. (Type the answer including the units)

Find the radius of a circle if its diameter is 15.9 centimeters. (Type the answer including the units)

Find the radius of a circle if its diameter is 12.8 feet. (Type the answer including the units)