Circumference
Area
Composite Shapes
Working Backwards
Word Problems
100
What are the formulas for circumference?
2(pi)r
(pi)d
100
What is the formula for area of a circle?
(pi)r^2
100
Find the area. Round to the nearest tenth.
121.9
100
Find the diameter when the circumference is 314.
d = 100
100
My garden is in the shape of a circle whose radius is 5 feet. I want to place stones around the outside edge. How many feet of stone will I need?
31.4 feet
200
Find the circumference of a circle whose diameter is 2 cm.
6.28 cm
200
Find the area of a circle when the radius is 30 mi.
2,826 mi2
200
Find the area. Round to the nearest tenth.
20.2 in2
200
Find the diameter when the circumference is 25.12
d = 8
200
My round dog bed needs a new cover. If the diameter of the dog bed is 5 feet, how many square feet of material will I need to make a new cover?
19.625 feet2
300
Find the circumference when the diameter is 15 in.
47.1 in
300
Find the area of a circle when the diameter is 8 in. Round to the nearest tenth.
50.2 in2
300
Find the area
136
300
Find the radius when the circumference is 50.24
r = 8
300
I'm painting a circular mural on my bedroom wall. The mural will measure 30 inches across. How many square inches of paint will I need to cover the mural background?
706.5 inches2
400
Find the circumference when the radius is 6.2 m .Round to the nearest tenth.
38.9 m
400
Find the area of a semi-circle when the diameter is 25 cm. Round to the nearest tenth.
245.3 cm2
400
Find the area. Round to the nearest tenth. 
157.2
400
Find the radius when the circumference is 15.7
r = 2.5
400
My grandmother likes to sew lace around her table clothes. The tablecloth is circular with a diameter of 60 inches and lace costs $.10 an inch. How much money will she spend on the lace?
$18.84
500
Find the circumference when the radius is 7.25 in. Round to the nearest tenth.
45.5 in
500
If the circumference of a circle is 113.04 in, what is its area? (Work backwards to find radius, then solve for area).
1017.36 in2
500
Find the area; Round to the nearest tenth.
67.2
500
Find the radius when the circumference is 8.635
r = 1.375
500
The diameter of a bicycle wheel is 17.5 inches. How far will the wheel travel after 3 turns?
164.85 inches