Circumference and Area of Circles

If the circumference of a circle is 62.83 cm, what is the radius?

• 8 cm

• 10 cm

• 12 cm

• 15 cm

What is the formula for the area of a circle?

• A = @@ ext{π}r^2@@

• A = 2 ext{π}r

• A = ext{π}d

• A = ext{π}r^3

What is the value of π (pi) approximately?

• 2.71

• 3.14

• 3.33

• 3.00

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

• 153.94 cm²

• 140.00 cm²

• 154.00 cm²

• 150.00 cm²

If a circle has an area of 50 cm², what is the radius?

• 2.5 cm

• 3.99 cm

• 5.5 cm

• 4.5 cm

What is the formula for the circumference of a circle?

• C = @@2 ext{π}r@@

• C = @@ ext{π}r^2@@

• C = @@rac{d}{2}@@

• C = @@ ext{π}d@@

What is the circumference of a circle with an area of 78.54 cm²?

• 25.12 cm

• 31.42 cm

• 37.68 cm

• 20.00 cm

How do you convert diameter to radius?

• r = @@d + 2@@

• r = @@d - 2@@

• r = @@d imes 2@@

• r = @@\frac{d}{2}@@

What is the area of a circle with a radius of 10 cm?

• 314.16 cm²

• 250 cm²

• 300 cm²

• 400 cm²

If the diameter of a circle is 10 m, what is the circumference?

• 25.12 m

• 31.42 m

• 20.00 m

• 15.70 m