Area and Circumference

Front

What is the radius of a circle?

Back

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

Front

What is the diameter of a circle?

Back

The diameter is the distance across the circle through its center, equal to twice the radius.

Front

What is the circumference of a circle?

Back

The circumference is the distance around the circle.

Front

What is the formula for the circumference of a circle?

Back

C = 2πr, where C is the circumference and r is the radius.

Front

What is the formula for the area of a circle?

Back

A = πr², where A is the area and r is the radius.

Front

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

Back

The diameter is 10 cm.

Front

If the diameter of a circle is 12 cm, what is the radius?

Back

The radius is 6 cm.

Front

What is the relationship between radius and diameter?

Back

The radius is half of the diameter.

Front

What is the area of a circle with a radius of 3 cm?

Back

A = π(3)² = 28.26 cm².

Front

What is the circumference of a circle with a radius of 4 cm?

Back

C = 2π(4) = 25.13 cm.