STAAR released questions on Circles

A circle has an area of approximately 28.26 square centimeters. Which measurement is closest to the radius of the circle in centimeters?

• 3 cm

• 6 cm

• 5 cm

• 9 cm

A sprinkler rotates and sprays water onto a lawn. The part of the lawn watered by the sprinkler is in the shape of a circle with the diameter shown in feet. Which measurement is closest to the area in square feet of the part of the lawn watered by the sprinkler?

• 1,231 ft²

• 44 ft²

• 615 ft²

• 154 ft²

A sundial has a circular base with a diameter of 90 feet as shown in the diagram. Which measurement is closest to the area of the circular base of the sundial in square feet?

• 3,627.9 ft²

• 282.6 ft²

• 141.3 ft²

• 6,358.5 ft²

A circle has a radius of 4.5 centimeters. Which measurement is closest to the circumference of the circle in centimeters?

• 14.13 cm

• 28.26 cm

• 63.59 cm

• 56.52 cm

The radius of circle S is half the radius of circle L. The radius of circle L is 8 millimeters. Which measurement is closest to the area of circle S in square millimeters?

• 50.24 mm²

• 25.12 mm²

• 200.96 mm²

• 12.56 mm²

The diameter of circle X is 15 centimeters. The diameter of circle Y is 20 centimeters. Which measurement is closest to the difference between the circumference of circle X and the circumference of circle Y in centimeters?

• 15.7 cm

• 7.85 cm

• 137 cm

• 31.4 cm

7.9(B) determine the circumference and area of circles. The head of a nail is circular, as shown. The head of this nail has a diameter of 6 millimeters. Which measurement is closest to the area of the head of this nail in square millimeters?

• 9.42 mm²

• 113.04 mm²

• 28.26 mm²

• 37.68 mm²

A circle has a diameter of 7.6 feet. Which measurement is closest to the circumference of the circle in feet?

• 23.9 ft

• 45.3 ft

• 47.7 ft

• 11.9 ft

An observatory is shaped like a cylinder standing on one of its bases with a dome on top. The diameter of the floor of the observatory is 64 feet, as shown in the diagram. Which measurement is closest to the circumference of the base of the observatory in feet?

• 200.96 ft

• 3,215.36 ft

• 100.48 ft

• 401.92 ft

A company's logo was designed using circles of 3 different sizes. The diameters of two of the circles are shown. Which measurement is closest to the area of the largest circle in square centimeters?

• 56.52 cm²

• 141.30 cm²

• 1,017.36 cm²

• 254.34 cm²