Circles, Area, and Composite Figures

The circumference of a circle is C inches. The diameter of a circle is 20 inches.

Which expression best represents the value of π?

A sundial has a circular base with a diameter of 100 feet as shown in the diagram. Which measurement is closest to the area of the circular base of the sundial in square feet (ft²)?

• 3,925 ft²

• 7,850 ft²

• 392.5 ft²

• 785 ft²

Which definition best describes π?

• The ratio of the circumference of a circle to its diameter

• The ratio of the circumference of a circle to its radius

• The radius of a circle multiplied by 2 times 3.14

• The diameter of a circle multiplied by 2 times 3.14

The radius of circle S is half the radius of circle L. The radius of circle L is 10 millimeters. Which measurement is closest to the area of circle S in square millimeters (mm²)?

• A. 31.4 mm²

• B. 62.8 mm²

• C. 78.5 mm²

• D. 94.2 mm²

A circle has a radius of 5.5 centimeters. Which measurement is closest to the circumference of the circle?

• A. 17.27 cm

• B. 34.54 cm

• C. 51.81

• D. 69.08

The figure is composed of two trapezoids. Measurements are given in feet. What is the area of the figure in square feet (ft²)?

• 11 ft²

• 15 ft²

• 20 ft²

• 26 ft²

A sidewalk in the shape of two triangles, a rectangle, and a square was built around the edge of a building as shown. What is the area of the sidewalk in square feet (ft²)?

• 110 ft²

• 125 ft²

• 150 ft²

• 180 ft²

Two congruent squares and a parallelogram were used to form the figure shown. What is the area of the figure in square meters (m²)?

• 21.8 m²

• 30.6 m²

• 34.8 m²

• 43.6 m²

The dimensions of a rectangular prism are given in the net shown. What is the total surface area of the rectangular prism in square inches (in²)?

• 168 in²

• 180 in²

• 198 in²

• 216 in²

A circle has a diameter of 20 inches. Which formula represents how to find the area of the circle?

• A. A = 20 (π²)

• B. A = π (10²)

• C. A = π (20²)

• D. A = 2(π)(10)