Circumference and Area of Circles

If my radius is 10ft, what is my diameter?

• 20ft

• 5ft

• 31.4ft

• 62.8ft

what is the circumference of this circle ?

• 3.14 cm 

• 37.68 cm

• 24 cm

• 68.4 cm

The radius of a circle is

• The measurement from the center of a circle to an edge of the circle.

• The measurement around the circle

• The measurement from and edge of the circle to another edge through the center

• A line perpendicular to the diameter of the circle

What is the area of this circle?

• 1385.44

• 2142.12

• 5541.77

• 1289.12

What is π ? (Best Choice)

• The ratio of the circumference of any circle to its diameter.

• Exactly 3.14

• Exactly 3.1415

• Exactly 3.141593

A circular window has a diameter of 24 inches.  A piece of metal is to go around the window for a frame. How long does the metal need to be? (Best Choice)

• 24π or about 75.36 in

• 12π or about 37.68 

• 576π or about 1,808.64 in

• 144π or about 452.16 in 

A center circle on a basketball court has a diameter of 12 feet.  How long is the line that wraps around the circle? (Best Choice)

• 6π or about 18.84 ft

• 12π or about 37.68 ft

• 36π or about 113.04 ft

• 144π or about 452.16 ft