Parts of a Circle
A line segment that goes from one side of the circle to the center.
Radius
The diameter of a circle is 11 feet. What is the circle's radius?
5.5 feet
The radius of a circle is 6 kilometers. What is the circle's circumference?
37.68km
The lens of a telescope has a diameter of 6 feet. What is the distance around the telescope lense?
18.84 ft
What is the formula for getting the diameter if given the radius.
d=2r
A line that goes from one side of the circle to the other and passes through the center.
Diameter
The radius of a circle is 4 feet. What is the circle's diameter?
8 ft
Lisa has a circular swimming pool. The pool has a diameter of 26 feet. What is the circumference of the pool in feet?
81.64ft
The circular mirror hanging on Neil's wall has a radius of 9 centimeters. What is the circumference?
56.52 cm
What is the formula for finding the circumference of a circle if given the diameter?
c = d x pi
The distance around the circle.
Circumference
The round base of a copper tea kettle has a diameter of 14 centimeters. What is the base's radius?
7 cm
A circular container has an opening with a radius of 4.2 inches. What is the circumference of the opening?
26.37in
A family room has a circular rug with a radius of 4 feet. What is the distance around?
25.12 ft
What is the formula for finding the circumference of a circle if given the radius?
c = 2r x pi
The line that is 1/2 of the diameter.
Radius
A merry-go-round has a circular platform with a radius of 12 meters. What is the platform's diameter?
24 m
Hugo attaches his A+ test to the refrigerator with a circular magnet. Out of curiosity, he measures the magnet and calculates that it has a diameter of 4 centimeters. What is the magnet's circumference?
12.56cm
Claudia drew a circle on the driveway with chalk. The diameter of that circle was 17 inches. What is the distance around the circle?
53.38in
What is the formula for finding the area of a rectangle?
A = l x w
The ratio of the Circumference to the diameter.
C/d or 3.14
The top of the small shield potion is 12.2 cm in diameter. What is the radius?
6.1 cm
The wheels on the golf cart on Fortnite are 12 feet in diameter. How many feet around is one of the tires?
37.68ft
The Dark Viking built a circular base with a radius of 4 feet. What is the distance around his base?
25.12 ft
What is the formula for the area of a triangle?
A = 1/2 x b x h