Show:
Circle Terms
Radius and Diameter
Circumference and Area
Real World Problems
Formulas
100

distance from the center of a circle to the edge

radius

100

The diameter is 10 inches. What is the radius?

5 inches

100

A circle has a diameter of 12.5 inches. What is the circumference in terms of pi?

12.5pi

100

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.

100

d/2 = 

radius

200

Aaron walks all the way around the outside of a circular field.

Circumference

200

The diameter is 25 feet. What is the radius?

12.5 feet

200

A circle has a diameter of 25 inches. What is the circumference rounded correctly to the nearest hundredth?

78.54 inches

200

A large Jeep has a tire with a radius of 18 inches. Find the circumference of the wheel

36(pi) or 113.04

200

finding diameter when you know the radius

2r

300

Miguel swims straight through the center of a circular pool from one end to the other.

Diameter

300

The circumference of the circle is 18pi inches. What is the radius.

9 inches

300

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.

300

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)

300

2(pi)r

Circumference

400

The longest chord in a circle.

Diameter

400

The area of this circle is 25pi inches squared. Find the radius

5 inches

400

A circle has a diameter of 16. What is the area in terms of pi.

8pi

400

A circular rug has a diameter of 20 inches. What is the exact area of the rug(in terms of pi)? 

100(pi)

400

Area of a circle

(pi)r^2


500

The constant of proportionality between the circumference and diameter of a circle

pi or (3.14)

500

A circle has an area of 144pi cm squared. Find the diameter.

24 inches

500

A circle has a circumference of 6pi square feet. What is the area?

9pi or 28.26 square feet

500

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

500

Finding diameter when given circumference

d = C/3.14