document.write( "Question 913729: In the figure above, the circle has center Y and the four shaded semicircles each have area 18π. What is the circumference of the circle?
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Algebra.Com's Answer #554806 by KMST(5328)\"\" \"About 
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\"r\"= radius of the small semicircles; \"R=4r\"= radius of the ;arge circle.
\n" ); document.write( "\"4%2A%281%2F2%29%2Api%2Ar%5E2=18pi\"= total area of the 4 semi-circles.
\n" ); document.write( "\"2pi%2Ar%5E2=18pi\"= total area of the 4 semi-circles.
\n" ); document.write( "\"r%5E2=18pi%2F2pi\"--->\"r%5E2=9\"--->\"r=3\"
\n" ); document.write( "So, \"R=4r=4%2A3=12\"
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\n" ); document.write( "Circumference of the circle =\"2pi%2AR=2pi%2A12=highlight%2824pi%29\"
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