To Find the Area of a Circle

Find the area of a sector bound by an arc of 72 degrees, if the radius of the circle is 7m.

• 123.2 square meters

• 153.9 square meters

• 38.5 square meters

• 30.8 square meters

Find the area of each sector.

• 52.4 in²

• 18,864 in²

• 60 in2

• 10.47 in

Papa Joe makes his famous rhubarb pie. If the pie has a diameter of 12in, and he cuts the pie into 8 slices, what is the area of 1 slice of pie?

• 14.13 in²

• 56.52 in²

• 4.71 in²

• 9.42 in²

The _____ is the distance from the center to any point on the circle.

• diameter

• radius

• π

• center

In the equation (x-3)²+(y+4)²=121, the radius of the circle is

• 242

• 11

• 121

• 22

Answer explanation

Because the 5 in the circumference is the diameter you need to take half of that (2.5) and then square it (2.5x2.5) = 6.25 and then multiply by 3.14 (6.25x3.14) = 19.63

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?

Answer explanation

You need to add the two diameters together first (11+3 =14), then divide by 2 to get the radius (14/2 = 7). Plug into the formula $A=\pi r^2$ (3.14)(7x7) = 153.86.

The areas of three circles are shown.

Which list shows the circles in order from greatest area to least area?

• Circle Z, circle Y, circle X

• Circle Y, circle Z, circle X

• Circle X, circle Z, circle Y

• Circle X, circle Y, circle Z

Tags

8.2.D