Circumference and Area

Front

What is the formula for the circumference of a circle?

Back

C = 2×π×r

Front

What is the formula for the area of a circle?

Back

A = π×r²

Front

What is the circumference of a circle?

Back

The distance around the circle.

Front

What is the diameter of a circle?

Back

A line through the center of a circle.

Front

What does the radius of a circle represent?

Back

The distance from the center of the circle to any point on its circumference.

Front

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

Back

C = 2×π×7 ≈ 43.98 cm.

Front

If the radius of a circle is 5 cm, what is the area?

Back

A = π×5² ≈ 78.54 cm².

Front

What is the relationship between diameter and radius?

Back

Diameter = 2 × Radius.

Front

What is π (pi)?

Back

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

Radius = Diameter ÷ 2.