Circles: Circumference and Area

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 formula for the circumference of a circle?

Back

Circumference (C) = π × diameter (d) or C = 2π × radius (r).

Tags

CCSS.7.G.B.4

Front

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

Back

The radius is 5 cm.

Tags

CCSS.7.G.B.4

Front

What is the area of a circle?

Back

The area (A) is calculated using the formula A = π × radius².

Tags

CCSS.7.G.B.4

Front

If the radius of a circle is 3 cm, what is its area?

Back

The area is 28.26 cm² (using π ≈ 3.14).

Tags

CCSS.7.G.B.4

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.

Tags

CCSS.HSG.C.A.2

Front

How do you calculate the circumference of a circle with a radius of 4 inches?

Back

Circumference = 2π × 4 = 25.12 inches (using π ≈ 3.14).

Tags

CCSS.7.G.B.4

Front

What is the relationship between diameter and radius?

Back

The diameter is twice the radius (d = 2r).

Tags

CCSS.7.G.B.4

Front

If a circle has a circumference of 31.4 cm, what is its diameter?

Back

The diameter is 10 cm (using C = πd).

Tags

CCSS.7.G.B.4

Front

What is the value of π (pi)?

Back

π (pi) is approximately 3.14.

Tags

CCSS.HSG.GMD.A.1