Circumference of Circles

Front

What is the formula for the circumference of a circle?

Back

C = πd or C = 2πr, where C is circumference, d is diameter, and r is radius.

Tags

CCSS.7.G.B.4

Front

If a circle has a diameter of 18 meters, what is its circumference?

Back

18π or about 56.52 m.

Tags

CCSS.7.G.B.4

Front

What is the radius of a circle with a diameter of 18 meters?

Back

9 meters.

Tags

CCSS.7.G.B.4

Front

What is the circumference of a circle with a radius of 4?

Back

8π or about 25.12.

Tags

CCSS.7.G.B.4

Front

Define the radius of a circle.

Back

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

Front

What is the relationship between diameter and radius?

Back

The diameter is twice the radius (d = 2r).

Tags

CCSS.7.G.B.4

Front

If the circumference of a circle is 88 inches, what is its diameter?

Back

The diameter is 28 inches (C = πd, so d = C/π).

Tags

CCSS.7.G.B.4

Front

What is the approximate value of π?

Back

π is approximately 3.14.

Tags

CCSS.HSG.GMD.A.1

Front

How do you calculate the circumference using the radius?

Back

Use the formula C = 2πr.

Tags

CCSS.7.G.B.4

Front

What is the circumference of a circle with a radius of 10?

Back

20π or about 62.83.

Tags

CCSS.7.G.B.4