Parts of Circle and Pi

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

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

• diameter

• radius

• π

• center

Which segment is a radius?

• LM

• DC

• BD

• ML

What is the diameter?

• 8

• 16

• 10

• 4

What is the radius?

• 18

• 72

• 38

• 14

Determine the radius of the penny

• 59.66 mm

• 9.5 mm

• 38 mm

• 119.32 mm

Find the circumference of a circle with a diameter of 11 millimeters.

• 34.6 mm

• 30 mm

• 25.3 mm

• 34.54 cm

Find the circumference of a circle with a radius of 12.5 mm.

• 37.68mm

• 18.84mm

• 78.54mm

• none of the above

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

• diameter

• radius

• π

• center

A _____ is half of a circle.

• circumference

• pi

• semicircle

•  composite figure