document.write( "Question 1097833: There are 3 circles that are externally tangent to each other. Find the perimeter around the shape if the radius of each circle is 3. \n" ); document.write( "
Algebra.Com's Answer #712250 by Edwin McCravy(20055)\"\" \"About 
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document.write( "The complete circumference of each of those circles with radius 3,\r\n" );
document.write( "is given by \r\n" );
document.write( "C = 2pr = 2p(3) = 6p\r\n" );
document.write( "So the sum of all three circumferences is 3 times that or\r\n" );
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document.write( "18p\r\n" );
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document.write( "However, from that, we must subtract the three arcs that are inside the\r\n" );
document.write( "green equilateral triangle that are shown below:\r\n" );
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document.write( "Since that is an equilateral triangle, each angle is 60°.\r\n" );
document.write( "Since 60° is 1/6th of 360°, each arc is 1/6th of a circumference,\r\n" );
document.write( "so we must subtract 1/6 of the total of the three circumferences,\r\n" );
document.write( "which will leave 5/6 of the 18p we\r\n" );
document.write( "calculated.\r\n" );
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document.write( "So the answer is 15p.\r\n" );
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document.write( "Edwin
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