Circumferences and Areas of Circles

1
Circumferences and Areas of Circles
COURSE 3 LESSON 8-8
The diameter of a small pizza is 24 cm. Find its
area. Round to the nearest tenth.
The radius of the pizza is 24 2, or 12 cm. Use
the radius to find the area.
The area of a small pizza is about 452.4 cm2.
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Circumferences and Areas of Circles
COURSE 3 LESSON 8-8
Find the area of the unshaded region of the
square tile with a circle inside of it, as shown
below. Round to the nearest tenth.
You can separate the figure into a circle and a
square.
Step 1 Find the area of the square.
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Circumferences and Areas of Circles
COURSE 3 LESSON 8-8
(continued)
Area of square s2
Step 2 Find the area of the circle.
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Circumferences and Areas of Circles
COURSE 3 LESSON 8-8
(continued)
Step 3 Subtract the area of the circle from the
area of the square.
The area of the shaded region is about 144 cm2
113.1 cm2 30.9 cm2.
8-8
5
Circumferences and Areas of Circles
COURSE 3 LESSON 8-8
Round to the nearest tenth. 1. Find the
circumference and area of the circle.
2. Find the area.
18.8 km 28.3 km2
273.0 in.2
8-8