Area and Circumference of Circles

Front

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

Back

C = 2πr or C = πd, where r is the radius and d is the diameter.

Tags

CCSS.7.G.B.4

Front

What is the distance around a circle called?

Back

Circumference.

Front

What is the radius of a circle?

Back

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

Front

What is the diameter of a circle?

Back

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

Tags

CCSS.HSG.C.A.2

Front

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

Back

31.4 inches (C = 2π(5)).

Tags

CCSS.7.G.B.4

Front

What is the area of a circle?

Back

A = πr², where r is the radius.

Tags

CCSS.7.G.B.4

Front

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

Back

5 cm (radius is half of the diameter).

Tags

CCSS.7.G.B.4

Front

How do you find the circumference of a circle with a diameter of 15 mm?

Back

C = π(15) or approximately 47.1 mm.

Tags

CCSS.7.G.B.4

Front

What is the relationship between radius and diameter?

Back

Diameter = 2 × Radius.

Tags

CCSS.7.G.B.4

Front

If a Ferris wheel has a diameter of 80 meters, how far does a rider travel in one complete rotation?

Back

Approximately 251.2 meters (C = π(80)).

Tags

CCSS.7.G.B.4