document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=403138>Question 403138</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Bob has to mix a solution of .67 herbicide and .46 herbicide to form 42 liters of a .55 solution. How much .67 solution does Bob use? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #285104 by </B><A HREF=/tutors/aboutme.mpl?userid=rvquartz><B>rvquartz(19)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rvquartz><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=rvquartz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=285104\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> based on the problem statement, we can create a mathematical model that says\r<BR>\n" );
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document.write( "x + y = 42 liters\r<BR>\n" );
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document.write( "where <BR>\n" );
document.write( "x = number of liters of the 67% strength solution<BR>\n" );
document.write( "y = number of liters of the 46% strength solution\r<BR>\n" );
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document.write( "also based on the problem statement, we can create another mathematical model that says\r<BR>\n" );
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document.write( "0.67x + 0.46y = 0.55(42) = 23.1 liters  (note: that is the amount of 'pure' 100% acid) \r<BR>\n" );
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document.write( "now we have two separate independent equations and two unknowns\r<BR>\n" );
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document.write( "we can substitute and solve\r<BR>\n" );
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document.write( "y = (42 - x) so\r<BR>\n" );
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document.write( "0.67x + 0.46(42 - x) = 23.1\r<BR>\n" );
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document.write( "0.67x - 0.46x + 19.32 = 23.1\r<BR>\n" );
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document.write( "0.21x + 19.32 = 23.1\r<BR>\n" );
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document.write( "0.21x = 3.78\r<BR>\n" );
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document.write( "x = 3.78/0.21\r<BR>\n" );
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document.write( "x = 18 liters of the 67% strength solution<BR>\n" );
document.write( "y = 24 liters of the 46% strength solution </SPAN>\n" );
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