document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=662906>Question 662906</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Copper that was 63% pure was melted together with copper that was 90% pure to make 18 kilograms of an alloy that was 75% pure. How many kilograms of each kind were used? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #412548 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=412548\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Copper that was 63% pure was melted together with copper that was 90% pure to make 18 kilograms of an alloy that was 75% pure. How many kilograms of each kind were used?<BR>\n" );
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document.write( "Equation:<BR>\n" );
document.write( "copper + copper = copper<BR>\n" );
document.write( "---<BR>\n" );
document.write( "0.63x + 0.90(18-x) = 0.75*18<BR>\n" );
document.write( "----<BR>\n" );
document.write( "63x + 90*18 - 90x = 75*18<BR>\n" );
document.write( "-27x = -15*18<BR>\n" );
document.write( "---<BR>\n" );
document.write( "x = 10 kg (amt of 63% alloy needed)<BR>\n" );
document.write( "---<BR>\n" );
document.write( "18-x = 8 kg (amt of 90% alloy needed)<BR>\n" );
document.write( "==============<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );