Circumference of a Circle

Front

What is the diameter of a circle?

Back

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

Front

If the diameter of a circle is 16 cm, what is the radius?

Back

The radius is 8 cm, which is half of the diameter.

Front

What is the formula to calculate the circumference of a circle?

Back

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

Front

If the radius of a circle is 10 ft, what is the circumference?

Back

Circumference = 2 × π × 10 ft ≈ 62.83 ft.

Front

What is the circumference of a circle with a diameter of 14 cm?

Back

Circumference ≈ 43.98 cm.

Front

If the diameter of a circle is 19 inches, what is the radius?

Back

The radius is 9.5 inches.

Front

What is π (pi)?

Back

π (pi) is a mathematical constant approximately equal to 3.14, representing the ratio of the circumference of a circle to its diameter.

Front

How do you convert diameter to radius?

Back

To convert diameter to radius, divide the diameter by 2.

Front

If a circle has a circumference of 31.4 cm, what is its diameter?

Back

Diameter = Circumference / π ≈ 10 cm.

Front

What is the relationship between diameter and circumference?

Back

The circumference is directly proportional to the diameter; as the diameter increases, the circumference increases.