document.write( "Question 1142265: Seven pencils are held together in hexagon shape by an elastic band. If the pencils are of diameter 7mm, what is the length of the band in this shape \n" ); document.write( "

Algebra.Com's Answer #762968 by Edwin McCravy(20067) $\"\"$ $\"About$

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document.write( "I think somebody is forgetting that the elastic band \r\n" );
document.write( "has straight parts and round parts.\r\n" );
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document.write( "OK, maybe they took the pencils to be hexagonal in cross-section\r\n" );
document.write( "and not circular.  I have both kind in my pencil collection.\r\n" );
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document.write( "Anyway I took the pencils to be circular in cross-section.\r\n" );
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document.write( "The elastic band is in green:\r\n" );
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document.write( "There are 6 straight parts and 6 round parts to the elastic band.\r\n" );
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document.write( "Each straight part is the length of two radii, as we see by this\r\n" );
document.write( "red rectangle. which is 1 diameter or 7mm.  So the 6 straight\r\n" );
document.write( "parts amount to 6×7mm or 42mm.\r\n" );
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document.write( "And as you can see by the 60° red sector,\r\n" );
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document.write( "Each round part of the elastic band is 1/6 of a circumference\r\n" );
document.write( "of one of the circles.  And there are 6 of them, so all 6\r\n" );
document.write( "total to one circumference of each circle, which is \r\n" );
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document.write( "So the answer is 6 straight parts which is 42mm plus 6 round\r\n" );
document.write( "parts which is  mm.\r\n" );
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document.write( "Answer  mm.\r\n" );
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document.write( "Edwin

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