Area and Circumference of Circles

Front

What is the area of a circle?

Back

The space inside the circle.

Front

What is the formula for the area of a circle?

Back

A = π × r²

Front

What is the radius of a circle?

Back

A line from the center to the side of the circle.

Front

What is the diameter of a circle?

Back

A line from side to side passing through the center.

Front

What is the circumference of a circle?

Back

The distance around a circle.

Front

How do you calculate the circumference of a circle?

Back

C = 2 × π × r or C = π × d, where d is the diameter.

Front

If the radius of a circle is 7 cm, what is the area?

Back

A = π × (7)² = 153.86 cm² (using π ≈ 3.14).

Front

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

Back

Radius = Diameter ÷ 2 = 10 cm ÷ 2 = 5 cm.

Front

What is the value of π (Pi) approximately?

Back

π ≈ 3.14.

Front

Find the area of a circle with a radius of 3 cm. Use 3.14 for Pi.

Back

A = π × (3)² = 28.26 cm².