Area and Circumference of a Circle

Front

What is the formula for the area of a circle?

Back

Area = π × r², where r is the radius.

Tags

CCSS.7.G.B.4

Front

What is the formula for the circumference of a circle?

Back

Circumference = 2 × π × r, where r is the radius.

Tags

CCSS.7.G.B.4

Front

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

Back

Area = π × (5 cm)² = 25π cm² ≈ 78.5 cm².

Tags

CCSS.7.G.B.4

Front

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

Back

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

Tags

CCSS.7.G.B.4

Front

What is the relationship between the radius and diameter of a circle?

Back

Diameter = 2 × Radius.

Tags

CCSS.7.G.B.4

Front

What is π (Pi)?

Back

Pi is a mathematical constant approximately equal to 3.14, representing the ratio of the circumference of a circle to its diameter.

Tags

CCSS.HSG.GMD.A.1

Front

If Circle A has a radius of 6 cm, what is the circumference?

Back

Circumference = 2 × π × 6 cm = 12π cm ≈ 37.68 cm.

Tags

CCSS.7.G.B.4

Front

Circle B has a radius of 4 cm. What is the area of Circle B?

Back

Area = π × (4 cm)² = 16π cm² ≈ 50.24 cm².

Tags

CCSS.7.G.B.4

Front

What happens to the area of a circle if the radius is doubled?

Back

The area increases by a factor of 4, since Area = π × (2r)² = 4πr².

Tags

CCSS.7.G.B.4

Front

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

Back

Area = π × (3 cm)² = 9π cm² ≈ 28.26 cm².

Tags

CCSS.7.G.B.4