Circle Terms
distance from the center of a circle to the edge
radius
The diameter is 10 inches. What is the radius?
5 inches
A circle has a diameter of 12.5 inches. What is the circumference in terms of pi?
12.5pi
A bicycle wheel has a radius of 1 foot. If the bicycle wheel rotates one time, what distance is travelled?
What is 2pi or 6.28 feet.
d/2 =
radius
Aaron walks all the way around the outside of a circular field.
Circumference
The diameter is 25 feet. What is the radius?
12.5 feet
A circle has a diameter of 25 inches. What is the circumference rounded correctly to the nearest hundredth?
78.54 inches
A large Jeep has a tire with a radius of 18 inches. Find the circumference of the wheel
36(pi) or 113.04
finding diameter when you know the radius
2r
Miguel swims straight through the center of a circular pool from one end to the other.
Diameter
The circumference of the circle is 18pi inches. What is the radius.
9 inches
A circle has a radius of 50 miles. What is the area of the circle TO THE NEAREST MILE?
What is 7,854 miles squared.
Matt is making a pizza. the radius of the pizza is 7 inches. Matt needs to figure out how much cheese he needs to cover the pizza. What is the area of the pizza?
1536.86 square inches or 49(pi)
2(pi)r
Circumference
The longest chord in a circle.
Diameter
The area of this circle is 25pi inches squared. Find the radius
5 inches
A circle has a diameter of 16. What is the area in terms of pi.
8pi
A circular rug has a diameter of 20 inches. What is the exact area of the rug(in terms of pi)?
100(pi)
Area of a circle
(pi)r^2
The constant of proportionality between the circumference and diameter of a circle
pi or (3.14)
A circle has an area of 144pi cm squared. Find the diameter.
24 inches
A circle has a circumference of 6pi square feet. What is the area?
9pi or 28.26 square feet
A circular field has a diameter of 28 yards. How many square feet is a quarter of the field? Provide your answer as decimal rounded to the nearest hundredth.
153.86 square yards
Finding diameter when given circumference
d = C/3.14