Classifying Circles

What is the formula for circumference of a circle given the diameter?

• C = π r

• C = 2 π r

• C = π d

• C = 2 π d

If the area of a circle is 25 π in² , then the diameter is?

• 10 in

• 5 in

• 25 in

• pi in

If the circumference of a circle is 22 π ft, what is the radius?

• 22 ft

• 11ft

• π ft

• no ft

If the circumference of a circle is 22π , what is the diameter?

• 22 ft

• 11 ft

• π ft

• 0 ft

If the circumference of a circle is 44 π feet, what is the radius?

• 22 ft

• 44 ft

• 33 feet

• 3.14 feet

The _____ is the distance from the center to any point on the circle.

• diameter

• radius

• π

• center

The distance across a circle through its center is called the _____.

• diameter

• radius

• π

• center

If you are given the diameter, how can you calculate the radius?

• Multiply the diameter by 2

• Divide the diameter by 2

• Add 2 to the diameter

• Subtract 2 from the diameter

Which segment is the diameter?

• AC

• BD

• LM

• CE

Which segment is a radius?

• LM

• DC

• BD

• ML