The radius of a circle is the distance from the center to any point on the circumference. The diameter is the distance from one side of the circle's circumference, through the center of the circle, to the opposite side.
14 millimeters
Practice makes perfect
We want to find the radius of the circle given its diameter. Let's recall the definitions of radius and diameter.
Radius: Distance from the center of the circle to any point on the circumference.
Diameter: Distance from one side of the circle's circumference, through the center of the circle, to the opposite side.
We are told that the diameter of this button is 28 millimeters. According to the definitions, the radius is half the diameter. Let's divide the diameter by 2!
28Ă· 2 = 14
This means that the radius is 14 millimeters.
