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Jack
10-10-2013, 11:52 AM
What is the area, of a circle with a circumference of 12\pi?

(A) 12\pi
(B) 24\pi
(C) 36\pi
(D) 144\pi


Thanks!

miranda
10-10-2013, 11:53 AM
The circumference is given by the formula C=2\pi r=12\pi \Rightarrow r= 6 /units/
The area is given by the formula A=\pi r^2=\pi (6)^2=36 \pi /units/ ^{2}
Therefore the correct answer is (C).

Hope these help!

Jack
10-10-2013, 11:53 AM
Thank you!