document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=836249>Question 836249</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a 30 lb bag of cement contains 35% cement and 65% sand. how much pure cement must be added to produce a cement mix that is 50% cement?<BR>\n" );
document.write( "i started to make a chart to help visualize, but i don't know where to plug in any of the values </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #504041 by </B><A HREF=/tutors/aboutme.mpl?userid=LinnW><B>LinnW(1048)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=LinnW><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=LinnW><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=504041\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Amount__|% as decimal|Total Pure<BR>\n" );
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document.write( "__30____|__0.35______|_0.35(30)<BR>\n" );
document.write( "__X_____|__1.00______|_1.00(X)<BR>\n" );
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document.write( "_(30+X)__|__0.50______|_0.50(30+X)\r<BR>\n" );
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document.write( "(30+X) is the amount of product of the new mix<BR>\n" );
document.write( "The total pure cement for our mix is<BR>\n" );
document.write( "equal to 0.35(30) + 1.00(X).<BR>\n" );
document.write( "The 0.35(30) is the amount of pure cement<BR>\n" );
document.write( "in the original bag.<BR>\n" );
document.write( "1.00 or 100% of the unknown X amount of cement<BR>\n" );
document.write( "is represented by 1.00(X)<BR>\n" );
document.write( "These two quantities together need to add<BR>\n" );
document.write( "up the new 50% mix represented by 0.50(30+X)<BR>\n" );
document.write( "So 0.35(30) + 1.00(X) = 0.50(30+X)<BR>\n" );
document.write( "10.50 + X = 15 + 0.5X<BR>\n" );
document.write( "add -0.5X to each side<BR>\n" );
document.write( "10.50 + 0.5X = 15<BR>\n" );
document.write( "add -10.50 to each side<BR>\n" );
document.write( "0.5X = 4.50<BR>\n" );
document.write( "X = 9<BR>\n" );
document.write( "Our new mix is a total of 39 pounds.<BR>\n" );
document.write( "The amount of pure cement in the new mix is 35% of 30 + 9 or<BR>\n" );
document.write( "10.50 + 9 , 19.5 pounds of cement.<BR>\n" );
document.write( "Since the new mix weighs 39 pounds, clearly 50% is cement.<BR>\n" );
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