Radius, Diameter, and Circumference

Front

What is the radius of a circle?

Back

The radius is the distance from the center of the circle to any point on its circumference.

Front

What is the diameter of a circle?

Back

The diameter is the distance across the circle through its center, equal to twice the radius.

Tags

CCSS.HSG.C.A.2

Front

How do you calculate the diameter if you know the radius?

Back

Diameter = 2 × Radius.

Tags

CCSS.7.G.B.4

Front

What is the circumference of a circle?

Back

The circumference is the distance around the circle.

Front

How do you calculate the circumference of a circle using the diameter?

Back

Circumference = Diameter × π (approximately 3.14).

Tags

CCSS.7.G.B.4

Front

How do you calculate the circumference of a circle using the radius?

Back

Circumference = 2 × π × Radius (approximately 3.14).

Tags

CCSS.7.G.B.4

Front

What is the value of π (Pi)?

Back

π (Pi) is approximately 3.14 and represents the ratio of the circumference of a circle to its diameter.

Tags

CCSS.HSG.GMD.A.1

Front

If the radius of a circle is 9 cm, what is the diameter?

Back

18 cm.

Tags

CCSS.7.G.B.4

Front

If the diameter of a circle is 14 cm, what is the circumference?

Back

Approximately 43.96 cm.

Tags

CCSS.7.G.B.4

Front

What happens if you divide the circumference of a circle by its diameter?

Back

You will always get π (Pi).

Tags

CCSS.7.G.B.4