Radius, Diameter, 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.

Front

How do you calculate the circumference of a circle?

Back

Circumference = π × diameter or Circumference = 2 × π × radius.

Front

If the diameter of a circle is 70 m, what is the radius?

Back

35 m

Front

If the radius of a circle is 24 m, what is the diameter?

Back

48 m

Front

What is the relationship between radius and diameter?

Back

The diameter is always twice the radius.

Front

What is the circumference of a circle with a diameter of 80 ft?

Back

Circumference = π × 80 ft ≈ 251.33 ft.

Front

If a bicycle tire has a diameter of 27 inches, what is the radius?

Back

13.5 inches

Front

What is the formula to find the radius if you know the circumference?

Back

Radius = Circumference / (2 × π).

Front

What is the formula to find the diameter if you know the radius?

Back

Diameter = 2 × radius.