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 5 cm, what is the circumference?

Back

Circumference = 2 × π × 5 cm ≈ 31.4 cm.

Front

What is the relationship between diameter and radius?

Back

Diameter = 2 × radius.

Front

If the diameter of a circle is 10 inches, what is the radius?

Back

Radius = diameter ÷ 2 = 10 inches ÷ 2 = 5 inches.

Front

What does the term 'perimeter' refer to in the context of circles?

Back

Perimeter refers to the circumference of the circle.

Front

If a circle has a circumference of 62.8 cm, what is its diameter?

Back

Diameter = Circumference ÷ π ≈ 62.8 cm ÷ 3.14 ≈ 20 cm.

Front

What is the circumference of a circle with a radius of 7 ft?

Back

Circumference = 2 × π × 7 ft ≈ 43.96 ft.

Front

What is the diameter of a circle if its circumference is 31.4 cm?

Back

Diameter = Circumference ÷ π ≈ 31.4 cm ÷ 3.14 ≈ 10 cm.

Front

If the radius of a circle is doubled, how does the circumference change?

Back

The circumference also doubles.

Front

What is the circumference of a circle with a diameter of 12 inches?

Back

Circumference = π × 12 inches ≈ 37.68 inches.