document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=113878>Question 113878</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many grams of pure silver must be mixed with 450grams of an alloy that is 10% copper in order to produce a sterling silver that is 7.5% copper? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #434729 by </B><A HREF=/tutors/aboutme.mpl?userid=filboi><B>filboi(35)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=filboi><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=434729\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I would assume that this problem only involves silver & copper. I think adding other metal in the equation is a little bit \"over-analyzing\" it since there is no mention of any other metal apart from the two.\r<BR>\n" );
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document.write( "Now to lower the concentration of copper, we would have to add more silver in the alloy so we're solving this problem from the silver's perspective.\r<BR>\n" );
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document.write( "Let<BR>\n" );
document.write( "s = pure silver to be added<BR>\n" );
document.write( "100% - 10%(copper content) = 90% = 0.90 = silver content in the original alloy<BR>\n" );
document.write( "100% - 7.5%(copper content) = 92.5% = 0.925 = silver content in the new alloy\r<BR>\n" );
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document.write( "Our equation is:\r<BR>\n" );
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document.write( "s + (0.90)(450 - s) = (0.925)(450)\r<BR>\n" );
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document.write( "Solving for s will give us 112.5g </SPAN>\n" );
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