Circumference and Area of Circles Flashcard

Front

What is the circumference of a circle?

Back

The circumference of a circle is the distance around it, calculated using the formula C = 2×π×r, where r is the radius.

Tags

CCSS.7.G.B.4

Front

What is the formula for Circumference?

Back

C = 2×π×r

Tags

CCSS.7.G.B.4

Front

What does 12 inches represent in a circle?

Back

12 inches represents the radius of the circle.

Front

What is the formula for the area of a circle?

Back

A = πr²

Tags

CCSS.7.G.B.4

Front

How do you find the area of a circle with a radius of 6 cm?

Back

A = π(6)² = 36π ≈ 113.04 cm².

Tags

CCSS.7.G.B.4

Front

What is the diameter of a circle?

Back

The diameter is twice the radius. If the radius is 3 cm, the diameter is 6 cm.

Tags

CCSS.7.G.B.4

Front

What is the relationship between diameter and radius?

Back

The diameter is equal to twice the radius: D = 2r.

Tags

CCSS.7.G.B.4

Front

If the circumference of a circle is 37.68 cm, what is the radius?

Back

Using C = 2×π×r, r = C/(2×π) = 37.68/(2×π) ≈ 6 cm.

Tags

CCSS.7.G.B.4

Front

What is π (pi)?

Back

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

Tags

CCSS.HSG.GMD.A.1

Front

How do you convert radius to diameter?

Back

Multiply the radius by 2: D = 2r.

Tags

CCSS.7.G.B.4