Radius and Diameter

Front

What is the Radius?

Back

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

Front

What is the Diameter?

Back

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

Front

How do you calculate the Diameter from the Radius?

Back

Diameter = 2 x Radius.

Front

How do you calculate the Radius from the Diameter?

Back

Radius = Diameter / 2.

Front

If the Radius is 7, what is the Diameter?

Back

Diameter = 2 x 7 = 14.

Front

If the Diameter is 22, what is the Radius?

Back

Radius = 22 / 2 = 11.

Front

What is the relationship between Radius and Diameter?

Back

The diameter is always twice the length of the radius.

Front

What is the formula for the area of a circle using the Radius?

Back

Area = π x (Radius)^2.

Front

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

Back

Circumference = 2 x π x Radius.

Front

If the Radius is 3, what is the area of the circle?

Back

Area = π x (3)^2 = 9π.