Area and Circumference (Circles)

Front

What is the formula for the circumference of a circle?

Back

Front

What is the formula for the area of a circle?

Back

Front

What is the diameter of a circle?

Back

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

Front

What is the radius of a circle?

Back

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

Front

What is the relationship between diameter and radius?

Back

Front

What is the circumference of a circle with a radius of 7 ft?

Back

The circumference is @@C = 2 ext{π}(7) ext{ ft} \\ C \\approx 43.98 ext{ ft}$$.

Front

What is the area of a circle with a radius of 5 ft?

Back

The area is @@A = ext{π}(5^2) ext{ ft}^2 \\ A \\approx 78.54 ext{ ft}^2$$.

Front

What does 'circumference' mean?

Back

Circumference is the distance around a circle.

Front

What does 'area' mean in the context of a circle?

Back

Area refers to the space contained within the circle.

Front

If a circle has a circumference of 31.4 ft, what is its radius?

Back

To find the radius, use the formula: @@C = 2 ext{π}r \\ r = rac{C}{2 ext{π}} = rac{31.4}{2 ext{π}} \\ r \\approx 5 ext{ ft}$$.