Radius and Diameter of Circles

Front

What is the definition of a radius?

Back

The distance from the center of a circle to any point on the circle.

Front

What is the definition of a diameter?

Back

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

Tags

CCSS.HSG.C.A.2

Front

If the radius of a circle is 5 cm, what is the diameter?

Back

10 cm

Tags

CCSS.7.G.B.4

Front

If the diameter of a circle is 12 m, what is the radius?

Back

6 m

Tags

CCSS.7.G.B.4

Front

What is the relationship between radius and diameter?

Back

The diameter is twice the length of the radius.

Tags

CCSS.7.G.B.4

Front

What is the formula to find the diameter if the radius is known?

Back

Diameter = 2 x Radius

Tags

CCSS.7.G.B.4

Front

What is the formula to find the radius if the diameter is known?

Back

Radius = Diameter / 2

Tags

CCSS.7.G.B.4

Front

If a circle has a diameter of 30 inches, what is its radius?

Back

15 inches

Tags

CCSS.7.G.B.4

Front

What is the circumference of a circle with a radius of 7 cm? (Use π ≈ 3.14)

Back

Circumference = 2πr = 2 x 3.14 x 7 = 43.96 cm

Tags

CCSS.7.G.B.4

Front

What is the area of a circle with a radius of 4 m? (Use π ≈ 3.14)

Back

Area = πr² = 3.14 x 4² = 50.24 m²

Tags

CCSS.7.G.B.4