document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1146352>Question 1146352</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A chemist has 20% and 60% solutions of acid available. How many liters of each solution should be mixed to obtain 25 liters of 28% acid solution? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #767622 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=767622\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x = the number of liters of the 20% solution.<BR>\n" );
document.write( "y = the number of liters of the 60% solution.\r<BR>\n" );
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document.write( "you want 25 liters of a 28% solution.<BR>\n" );
document.write( "that would require .28 * 25 = 7 liters of acid.\r<BR>\n" );
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document.write( "you have two equatons that need to be solved simultaneously.<BR>\n" );
document.write( "they are:\r<BR>\n" );
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document.write( "x + y = 25<BR>\n" );
document.write( ".2x + .6y = 7\r<BR>\n" );
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document.write( "multiply both sides of the first equation by .2 and leave the second equation as is to get:\r<BR>\n" );
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document.write( ".2x + .2y = 5<BR>\n" );
document.write( ".2x + .6y = 7\r<BR>\n" );
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document.write( "subtract the first equation from the second to get:\r<BR>\n" );
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document.write( ".4y = 2\r<BR>\n" );
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document.write( "solve for y to get y = 5\r<BR>\n" );
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document.write( "since x + y = 25, then x = 20\r<BR>\n" );
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document.write( "your solution is that you need 20 liters of the 20% solution plus 5 liters of the 60% solution to get 25 liters of the 28% solution.\r<BR>\n" );
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document.write( ".2 * 20 + .6 * 5 = 7\r<BR>\n" );
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document.write( "7/25 = .28 = 28%\r<BR>\n" );
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document.write( " </SPAN>\n" );
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