Circumference and Area of Circles

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

• 2 * pi * radius

• radius * radius

• 2 * radius

• pi * radius

Tags

CCSS.7.G.B.4

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

• 15π cm

• 20π cm

• 25π cm

• 10π cm

Tags

CCSS.7.G.B.4

What is the formula to find the area of a circle?

• A = 2πr

• A = πd

• A = πr^2

• A = πr

Tags

CCSS.7.G.B.4

If the diameter of a circle is 12 cm, what is its circumference?

• 24.141

• 37.699

• 18.85

• 9.42

Tags

CCSS.7.G.B.4

If the radius of a circle is 8 cm, what is its area?

• 32π cm^2

• 16π cm^2

• 128π cm^2

• 64π cm^2

Tags

CCSS.7.G.B.4

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

• The diameter of a circle is twice the length of its radius.

• The diameter of a circle is equal to the length of its radius.

• The diameter of a circle is half the length of its radius.

• The diameter of a circle is three times the length of its radius.

Tags

CCSS.HSG.C.A.2

If the circumference of a circle is 30 cm, what is its radius?

• 3 cm

• 6 cm

• 10 cm

• 4.77 cm

Tags

CCSS.7.G.B.4

If the area of a circle is 64 sq cm, what is its radius?

• 2 cm

• 6 cm

• 8 cm

• 4 cm

Tags

CCSS.7.G.B.4

If the circumference of a circle is 18π cm, what is its diameter?

• 9 cm

• 36 cm

• 18 cm

• 12 cm

Tags

CCSS.7.G.B.4

If the area of a circle is 100π sq cm, what is its radius?

• 15 cm

• 5 cm

• 20 cm

• 10 cm

Tags

CCSS.7.G.B.4