Circles: Area & Circumference

Front

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

Back

C = 2πr or C = πd

Front

What is the formula to find the area of a circle?

Back

A = πr²

Front

What does circumference mean?

Back

The distance around a circle.

Front

What does area mean?

Back

The amount of space inside a shape.

Front

If the radius of a circle is 5 meters, what is the circumference?

Back

31.42 meters (C = 2πr = 2π(5))

Front

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

Back

5 meters (Radius is half of the diameter.)

Front

What is the diameter of a circle?

Back

The distance across the circle through the center.

Front

If the area of a circle is 78.5 m², what is the radius?

Back

5 meters (A = πr², r = √(A/π))

Front

What is the relationship between diameter and radius?

Back

Diameter is twice the radius (d = 2r).

Front

A circular garden has a radius of 3 meters. What is its area?

Back

28.27 m² (A = πr² = π(3)²)