Circumference & Area of Circles

Front

What is the formula for the circumference of a circle using the radius?

Back

C = Pi * 2 * r

Tags

CCSS.7.G.B.4

Front

What is the formula for the area of a circle?

Back

A = Pi * r^2

Tags

CCSS.7.G.B.4

Front

What does 'r squared' mean in the area formula?

Back

r times r

Tags

CCSS.7.G.B.4

Front

What is the relationship between diameter and radius?

Back

Diameter is twice the radius.

Tags

CCSS.7.G.B.4

Front

What is the value of Pi (π) approximately?

Back

3.14

Tags

CCSS.HSG.GMD.A.1

Front

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

Back

Radius = Diameter / 2

Tags

CCSS.7.G.B.4

Front

If a circle has a radius of 5 inches, what is its circumference?

Back

C = 31.4 inches (C = Pi * 2 * r = 3.14 * 2 * 5)

Tags

CCSS.7.G.B.4

Front

If a circle has a radius of 7 inches, what is its area?

Back

A = 153.86 square inches (A = Pi * r^2 = 3.14 * 7^2)

Tags

CCSS.7.G.B.4

Front

What is the diameter of a circle with a radius of 10 inches?

Back

Diameter = 20 inches (Diameter = 2 * r)

Tags

CCSS.7.G.B.4

Front

How do you convert diameter to radius?

Back

Divide the diameter by 2.

Tags

CCSS.7.G.B.4