Answer: 12pi millimeters
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Explanation:
The circumference of a circle is the distance around the full circle, aka the perimeter.
The formula for the circumference is
C = pi*d
where d is the diameter. The radius given is 6, so the diameter is 2*6 = 12.
The circumference, is therefore:
C = pi*d
C = pi*12
C = 12pi millimeters
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As a slight alternative, you can use this formula
C = 2*pi*r
with r = 6 as the radius
C = 2*pi*r
C = 2*pi*6
C = 2*6*pi
C = 12pi
We get the same answer as before.
