Unit 8 Circles and Proportional Reasoning
Mathematician_________________________Date __/__/__ Hour ___
I can calculate circumference and area of a circle.
I can calculate arc length and area of a sector of a circle.
Find the circumference and area of each circle. (Use 3.14 for 𝝅.)
Round answers to the nearest hundredths.
1)
C = ________________________
14 cm A = ________________________
2)
C = ________________________
1.5 cm A = ________________________
3)
Find the Arc Length and Area of each shaded Sector. (Use 3.14 for 𝜋.)
Round answers to the nearest hundredths.
Arc Length =
Area of Sector =
4)
Pam served her apple pie on a 13 inch diameter dish. She wanted to tie a ribbon
around the dish to make it a little more festive. How long does the ribbon need to be
in order to fit around the dish?
5)
How many square inches of crust would it take to cover the bottom of a pie dish
with a 15 inch diameter?
6)
The distance around the ferris wheel in Chicago is 471 feet. What is the
distance across the ferris wheel?
7)
The center circle on a high school gymnasium floor has a diameter of 5 feet, if
Mr. Silmser walked around the circle 8 times, how far did he walk?
8)
Judy’s house sits in the middle of her triangle-shaped yard. Scruffy, her dog, has a
leash that is anchored in the corner of her yard and reaches to her front door. The leash is
25 ft long.
a) What is the area that Scruffy is able to run around in?
b) If Scruffy runs along a curved line, what is the distance she will travel, from fence to
fence?
Answers:
1)
C = 43.96 cm
2)
C = 9.42 cm
4)
40.82 in
5)
176.63 in
7)
125.6 ft
8a)
327.08 ft
2
A = 153.86 cm
2
A = 7.07 cm
2
2
3)
Arc Length: 5.65 in
6)
150 ft
8b)
26.17 ft
Area of Sector: 8.24 in
2