Circles and Composite Figures

Multiple Choice

Which of the following statements best describes a circle?

• A circle is a two-dimensional figure measured differently than polygons and quadrilaterals.

• A circle is a three-dimensional figure similar to a sphere.

• A circle has straight sides like polygons and quadrilaterals.

• A circle is only found in mathematical diagrams.

Multiple Choice

Which term describes the distance from the center of a circle to any point on the circle?

• Diameter

• Radius

• Circumference

• Chord

Fill in the Blanks

The diameter of a circle is

times the radius.

Multiple Select

Select all statements that are true about the diameter of a circle.

• It passes through the center of the circle.

• It is equal to the radius.

• It has endpoints on the circle itself.

• It is twice the radius.

Multiple Choice

Find the diameter of a circle with a radius of 7 inches.

• 7 inches

• 14 inches

• 21 inches

• 3.5 inches

Multiple Choice

What is the mathematical name for the ratio of the circumference to the diameter of a circle?

• Pi

• Tau

• Epsilon

• Sigma

Multiple Select

Which of the following are valid formulas for finding the circumference of a circle?

• C = πd

• C = 2πr

• C = πr^2

• C = d^2π

Fill in the Blanks

The circumference of a circle with a diameter of 9 inches is

inches (rounded to two decimal places).

Fill in the Blanks

Find the circumference of a circle with a radius of 2.5 yards. The circumference is

yards.

Multiple Choice

A circle has a radius of 8 inches. What is its circumference, rounded to the nearest inch?

• 25 inches

• 50 inches

• 64 inches^2

• 201 inches

Multiple Choice

Which formula is used to find the area of a circle?

• A = πr^2

• A = 2πr

• A = πd

• A = r^2

Multiple Choice

A button has a diameter of 20 millimeters. What is the area of the button? Use 3.14 as an approximation of π.

• 62.8 mm²

• 314 mm²

• 400 mm²

• 1256 mm²

Fill in the Blanks

The formula to find the circumference of a circle is C = π ×

.

Multiple Select

Which of the following steps are necessary to find the perimeter of the composite figure shown?

• Identify simpler shapes within the figure

• Calculate the exterior side lengths

• Add the exterior side lengths together

• Multiply the perimeters by π

Multiple Choice

Which formula would you use to find the circumference of a semicircle if the diameter is given?

• C = πr

• C = πd

• C = 2πr

• C = πr^2

Multiple Choice

Which of the following are necessary steps to find the area of the figure shown below (with two semi-circles and a square)?

• Add the area of the square and the area of the circle formed by the two semi-circles

• Multiply the area of the square by the area of the circle

• Add the area of the square and the area of one semi-circle

• Subtract the area of the square from the area of the circle

Fill in the Blanks

Pi is often approximated by the values 3.14 and

.

(The answer is a fraction)