Area & Circumference of Circles

Front

What is the formula for the circumference of a circle?

Back

C = 2πr, where C is the circumference and r is the radius.

Tags

CCSS.7.G.B.4

Front

What is the formula for the area of a circle?

Back

A = πr², where A is the area and r is the radius.

Tags

CCSS.7.G.B.4

Front

What is the circumference of a semicircle?

Back

C = πr + 2r, where r is the radius of the semicircle.

Tags

CCSS.7.G.B.4

Front

What is the area of a semicircle?

Back

A = (1/2)πr², where r is the radius of the semicircle.

Tags

CCSS.7.G.B.4

Front

If the radius of a circle is 7 cm, what is its circumference?

Back

C = 2π(7) ≈ 43.98 cm.

Tags

CCSS.7.G.B.4

Front

If the radius of a circle is 7 cm, what is its area?

Back

A = π(7)² ≈ 153.94 cm².

Tags

CCSS.7.G.B.4

Front

What is the relationship between diameter and radius?

Back

Diameter (d) = 2 × Radius (r).

Tags

CCSS.7.G.B.4

Front

What is the value of π (pi) approximately?

Back

π ≈ 3.14.

Tags

CCSS.HSG.GMD.A.1

Front

How do you convert the area from square centimeters to square meters?

Back

Divide the area in cm² by 10,000.

Tags

CCSS.5.MD.A.1

Front

What is the circumference of a circle with a diameter of 10 inches?

Back

C = πd = π(10) ≈ 31.4 inches.

Tags

CCSS.7.G.B.4