document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1084401>Question 1084401</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A roll of paper has an external diameter of 3' and internal diameter of 8\".  The paper is .005\" thick.  Determine length of paper. \r<BR>\n" );
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document.write( "Answer given: 16130 ft. \r<BR>\n" );
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document.write( "My attempt: \r<BR>\n" );
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document.write( "Volume of hollow cylinder:  pi(R + r)(R - r)   R = larger radius, r = smaller radius. \r<BR>\n" );
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document.write( "Let l = length. \r<BR>\n" );
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document.write( "l * .005 = pi(18 + 4)(18 - 4) \r<BR>\n" );
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document.write( "l = pi / .005 = pi(18 + 4)(18 - 4) \r<BR>\n" );
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document.write( "l = pi(18 + 4)(18 - 4) / .005 \r<BR>\n" );
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document.write( "l = pi(324 - 72 + 72 - 16) / .005 \r<BR>\n" );
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document.write( "l = pi(308 / .005) \r<BR>\n" );
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document.write( "l  = pi * 61600 \r<BR>\n" );
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document.write( "l = 193522.96 = 193523 in. = 16126.9166 = 16127 ft. \r<BR>\n" );
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document.write( "Where am I incorrect?   Non-homework.\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #698502 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=698502\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A roll of paper has an external diameter of 3' and internal diameter of 8\".  The paper is .005\" thick.  Determine length of paper. \r<BR>\n" );
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document.write( "Answer given: 16130 ft. <BR>\n" );
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document.write( "OD - ID = 36 - 8 = 28 inches --> r = 14 inches<BR>\n" );
document.write( "14/0.005 = 2800 turns.<BR>\n" );
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document.write( "Average diameter = (36+8)/2 = 22 inches<BR>\n" );
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document.write( "22*pi*2800 = 193522 inches<BR>\n" );
document.write( "= 16127 feet<BR>\n" );
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