11-8 Area of Circles
Find the area of each circle. Round to the nearest tenth.
The area is about 50.3 square centimeters.
50.3 cm
2
The area is about 706.9 square inches.
706.9 in
2
The area is about 78.5 square miles.
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78.5 mi
2
Page 1
The area is about 706.9 square inches.
11-8 Area2 of Circles
706.9 in
The area is about 78.5 square miles.
78.5 mi
2
The area is about 227.0 square feet.
227.0 ft
2
The area is about 66.5 square centimeters.
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66.5 cm
2
Page 2
The area is about 227.0 square feet.
11-8 Area2 of Circles
227.0 ft
The area is about 66.5 square centimeters.
66.5 cm
2
The area is about 323.7 square meters.
2
323.7 m
radius = 9.6 feet
The area is about 289.5 square feet.
289.5 ft
2
diameter = 24.8 meters
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The area is about 289.5 square feet.
11-8 Area2 of Circles
289.5 ft
diameter = 24.8 meters
The area is about 483.1 square meters.
2
483.1 m
diameter =
The radius is half the diameter, so 11
or 5.75.
The area is about 103.9 square yards.
2
103.9 yd
radius =
The area is about 42.2 square miles.
42.2 mi
2
LAWN CARE Lauren has a sprinkler positioned in her lawn that directs a 12-foot spray in a circular pattern. About
how much of the lawn does the sprinkler water if there is a rectangular flower bed 3 feet by 6 feet that is also in the
path of the spray?
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The area is about 42.2 square miles.
11-8 Area2 of Circles
42.2 mi
LAWN CARE Lauren has a sprinkler positioned in her lawn that directs a 12-foot spray in a circular pattern. About
how much of the lawn does the sprinkler water if there is a rectangular flower bed 3 feet by 6 feet that is also in the
path of the spray?
Find the areas of the circle and of the rectangle. Then subtract the area of the rectangle from the area of the circle..
So, the sprinkler waters about 452.4
434.4 ft
18 or about 434.4 square feet of the lawn.
2
What is the area of the CD shown below? Round to the nearest tenth.
Find the areas of the larger circle and of the smaller circle. Then subtract the area of the smaller circle from the
area of the larger circle.
So, the CD is about 113.1
1.8 or about 111.3 square centimeters.
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2
111.3 cm
Page 5
So, the sprinkler waters about 452.4
18 or about 434.4 square feet of the lawn.
11-8 Area2 of Circles
434.4 ft
What is the area of the CD shown below? Round to the nearest tenth.
Find the areas of the larger circle and of the smaller circle. Then subtract the area of the smaller circle from the
area of the larger circle.
So, the CD is about 113.1
1.8 or about 111.3 square centimeters.
2
111.3 cm
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