Parts of a Circle Circumference and Area

Find Circumference. Watch the units.

• 28.26 ft²

• 28.26 ft

• 28.26

• 56.52 ft

Find Circumference. Round to the nearest hundredths.

• 40.69 yd

• 5.65 yd

• 11.30 yd

• 22.61 yd

What is line CB called?

• Circumference

• Diameter

• Radius

• Chord

What is this symbol called?

• pi

• sigma

• radius

• omega

Which of these formulas can be used for area?

In words, describe this formula

• The area of a circle is equal to pi times the radius squared

• The circumference of a circle is equal to the pi times the diameter.

• The circumference of a circle is equal to pi times the radius squared

• The area of a circle is equal to pi times the diameter

Choose the answer which best describes how these formulas are related to each other.

• They both solve for circumference. In the first formula it uses diameter, in the second formula it uses two times the radius, which is the same thing as diameter.

• They both solve for circumference, in the first uses diameter and the second uses pi.

• They both solve for area. In the first formula it uses diameter, in the second formula it uses two times the radius, which is the same thing as diameter.

• They both use circumference to solve for pi. One uses radius, the other uses diameter.

Find Circumference. Watch the units.

• 37.68 m²

• 37.68 m

• 18.84 m

• 18.84 m²

Find Circumference. Round to nearest hundredths

• 14.13 km

• 56.52 km

• 28.26 km

• 63.59 km

Find Circumference. Leave answer in terms of pi (π).

• 36π

• 9π

• 4.5π

• 18π