Area of a Circle and a Sector

The measure of central angle XYZ is 1.25pi radians. What is the area of the shaded sector?

40pi units2

The circular face of a watch has an area that measures between 800 and 900 square millimeters. What could be the radius of the watch face? Use 3.14 for Pi.

16 mm

A circular garden with a radius of 8 feet is surrounded by a circular path with a width of 3 feet. What is the approximate area of the path alone? Use 3.14 for Pi.

178.98 ft2

What is the area of the shaded sector of the circle?

B

Line segment WX is the radius of circle X, and line segment ZY is the radius of circle Y. Points W, X, C, Y, and Z are all on line segment WZ. What is the area of circle C, which passes though points W and Z?

C

Point G is the center of the small circle. Point X is the center of the large circle. Points G, H, and X are on line segment GX. What would be the area of a new circle that has line segment GX as its diameter?

C

Fiona draws a circle with a diameter of 14 meters. What is the area of Fiona's circle?

D

In circle G, r = 3 units. Maria draws a circle with double the area of circle G. What is the area of Maria's circle?

D

In circle V, r = 14ft. What is the area of circle V?

D

In the figure, angle ZYX is measured in degrees. The area of the shaded sector can be determined using the formula StartFraction measure of angle Z Y X Over 360 degrees EndFraction (pi r squared). Which best explains the formula?

The central angle measure of the sector divided by the total angle measure of a circle multiplied by the area of the circle will yield the area of the sector.