document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1208989>Question 1208989</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A 20-pound bag of Economy brand cement mix contains 25% cement and 75% sand. How much pure cement must be added to produce a cement mix that is 40% cement?\r<BR>\n" );
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document.write( "I think the equation should look like this:\r<BR>\n" );
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document.write( "%•amount + %•amount = %(mixture)\r<BR>\n" );
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document.write( "0.25(20) + 0.75(x) = 0.40(x + 20)\r<BR>\n" );
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document.write( "Is this correct? \r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #847798 by </B><A HREF=/tutors/aboutme.mpl?userid=MathTherapy><B>MathTherapy(10551)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathTherapy><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=MathTherapy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=847798\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "A 20-pound bag of Economy brand cement mix contains 25% cement and 75% sand. How much pure cement must be added to produce a cement mix that is 40% cement?\r\n" );
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document.write( "I think the equation should look like this:\r\n" );
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document.write( "%•amount + %•amount = %(mixture)\r\n" );
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document.write( "0.25(20) + 0.75(x) = 0.40(x + 20)\r\n" );
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document.write( "Is this correct? \r\n" );
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document.write( "No, it's NOT.\r\n" );
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document.write( "Initial amount of cement (C): .25(20)\r\n" );
document.write( "Amount of cement (C) to be added: 100%, or 1(C) \r\n" );
document.write( "Resulting CEMENT (C) in final mixture: .4(20 + C)\r\n" );
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document.write( "Cement + Cement = Cement\r\n" );
document.write( ".25(20) + 1(C) = .4(20 + C) ===> .25(20) + C = .4(20 + C)\r\n" );
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document.write( "Now, solve for C, the amount of cement to be added.</PRE> </SPAN>\n" );
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