Definitions
What is the definition of a circle?
Is the set of all points in a plane that are the same distance from a point called the center.
What is the equation to find the radius from the diameter?
What is the equation to find diameter from the radius?
d = 2r
What are the TWO equations for circumference?
C=2*pi*r OR C=pi*d
What is the equation to find the area of a circle?
A=pi*r^2
What is the definition of the radius?
The measurement from the center of the circle to any point on the edge of the circle
Find the radius if the diameter is 10 in.
r = 5 in
Find the diameter if the radius is 2 mm.
d = 4 mm
The diameter of a circle is 2 feet. What is the circle's circumference?
6.28 ft
r= 2 cm
12.56 square cm
What is the definition of diameter?
The distance ACROSS a circle THROUGH the center
Find the radius if the diameter is 32.2 yds.
r=16.1
Find the diameter if the radius if 45.2 cm.
90.4 cm
The radius of a circle is 2 centimeters. What is the circle's circumference?
12.56 cm
d=42.1in
A = 1,391.3 square inches
Diameter is twice the radius, radius is half the diameter
Which has a larger radius, a circle with a radius of 13 m or a circle with a diameter of 16 m?
Circle with a radius of 13 m.
Find the diameter of a circle with a radius of 5342.2 in.
10,684.4 in
d= 10.2 yd
32.0 yd
At a carnival, Kendra gets to spin a prize wheel. It has a diameter of 16 inches. What is the prize wheel's area?
200.96 square inches
What is the definition of the circumference? How is it different from the area?
Circumference: The distance AROUND the circle.
Area: The total amount of space that the circle takes up.
Which has a larger radius, a circle with a diameter of 23.2 in or a circle with a radius of 11.5 in?
Circle with a diameter of 23.2 in
Which has a large diameter? A circle with a radius of 12.3 cm or a circle with a diameter of 22.4 cm.
Circle with radius of 12.3 cm
Which one has a bigger circumference? r=4.1 in or d=3.2 in
r=4.1 in, C=25.7 in
In the circus, a tiger has been trained to jump through a ring of fire that has a radius of 4 yards. What is the ring's circumference?
12.56 yds