document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1136787>Question 1136787</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A rectangular iron pipe has an external dimention 12cm and 10cm with the iron being 1cm thick. The mass of 1cm^3 of cast iron is 7.2g. Calculate the mass of 2-meter length of the pipe. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #754613 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52872)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=754613\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .\r<BR>\n" );
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document.write( "Now the problem formulation is IDEAL.\r<BR>\n" );
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document.write( "<U>Solution</U>\r<BR>\n" );
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document.write( "The mass of the pipe is the product of its volume and the metal density.\r\n" );
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document.write( "The volume of the metal part is equal to the volume of the rectangular prism of the \"height\" of 2 meters \r\n" );
document.write( "with the cross section dimensions 12 and 10 centimeters MINUS the volume of the interior empty part, which is the rectangular prism \r\n" );
document.write( "of the same \"height\" of 2 meters and with the cross section dimensions 12 - 2*1 = 10 and 10-2*1 = 8 centimeters.\r\n" );
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document.write( "So, the volume of the metal is\r\n" );
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document.write( "    V = 200*12*10 - 20*10*8 = 22400 cubic centimeters.\r\n" );
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document.write( "The mass of the iron is  7.2*22400 = 161280 grams = 161.280 kilograms.    <U>ANSWER</U>.\r\n" );
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document.write( "Solved.\r<BR>\n" );
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document.write( "Math problem, &nbsp;correctly formulated and presented, &nbsp;is and should be a piece of art.\r<BR>\n" );
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document.write( "Every word must be on its right place and correctly used.  &nbsp;All the words should be correctly placed and connected each with others.<BR>\n" );
document.write( "No ambiguity is allowed. &nbsp;No discontinuities or gaps in logic line are allowed. &nbsp;No excessive words are allowed.\r<BR>\n" );
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document.write( "Formulation of Math problem is an art and a science.\r<BR>\n" );
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document.write( "Learn using good examples from good sources . . .  \r<BR>\n" );
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document.write( "One very wise scientist and teacher said once that problems for students are the same and play the same role as the fair tales for children\r<BR>\n" );
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document.write( "- via such problems the students learn the world around.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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