Circumference of Circles

Front

What is the definition of circumference?

Back

The distance around the circle.

Front

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

Back

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

Front

If the radius of a circle is 5.8 cm, what is the circumference?

Back

36.4 cm.

Front

What is the definition of diameter?

Back

The distance across the circle through the center.

Front

If the circumference of a circle is 157 cm, what is the diameter?

Back

50 cm.

Front

What is the relationship between diameter and radius?

Back

Diameter = 2 × radius.

Front

If the circumference of a circle is 25.12 cm, what is the diameter to the nearest centimeter?

Back

8 cm.

Front

What is π (pi) approximately equal to?

Back

3.14.

Front

How do you find the radius if you know the circumference?

Back

Radius = Circumference / (2 × π).

Front

What is the circumference of a circle with a diameter of 10 cm?

Back

31.4 cm.