document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=188966>Question 188966</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A metallurgist needs to make 12.4 lb. of an alloy containing 50% gold. He is going to melt and combine one metal that is 60% gold with another metal that is 40% gold. How much of each should be used? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #141720 by </B><A HREF=/tutors/aboutme.mpl?userid=Mathtut><B>Mathtut(3670)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Mathtut><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=141720\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x and y be the amounts of 60% and 40% gold respectively<BR>\n" );
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document.write( "x+y=12.4...........eq 1<BR>\n" );
document.write( ".6x+.4y=.5(12.4)...eq 2<BR>\n" );
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document.write( "rewrite eq 1 to x=12.4-y and plug into eq 2<BR>\n" );
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document.write( ".6(12.4-y)+.4y=6.2<BR>\n" );
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document.write( "7.44-.6y+.4y=6.2<BR>\n" );
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document.write( "-.2y=-1.24<BR>\n" );
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document.write( "y=6.2 pounds of 40% gold<BR>\n" );
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document.write( "x=12.4-6.2=6.2 pounds of 60% gold<BR>\n" );
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document.write( "equal proportions makes perfect sense....since 50% is right in the middle of 40% and 60% </SPAN>\n" );
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