document.write( "Question 1101923: Three curtain rods, viewed from a sideways view, each have a diameter 3 cm, and are bound together by a band. The curtain rods (circles) are placed so there are two on the bottom and one on top of those two, in the middle, and the three resemble a triangle). The band goes around the three rods, but does not follow the shapes of the circles perfectly. The band becomes \"taut\" when it is not touching any part of the circles. Find the length of the band, in cm. \n" ); document.write( "

Algebra.Com's Answer #716545 by ikleyn(52798) $\"\"$ $\"About$

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document.write( "Obviously, the centers of the rods (in the section) form equilateral triangle with the side length of 3 cm.  (3 cm = 1.5 cm + 1.5 cm).\r\n" );
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document.write( "So, add 3 + 3 + 3 = 9 centimeters for the length of the 3 linear elements of the band. \r\n" );
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document.write( "Then add to it three times the length of the arc of the circle of the radius 1.5 cm and the central angle of 120 degrees.\r\n" );
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document.write( "So, the final answer is   =  centimeters.\r\n" );
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