document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=277315>Question 277315</A>: <I><SPAN STYLE=\"word-break: break-all;\"> one acetic acid solution is 70% water and another is 30% water. how many liters of each solution should be mixed to produce 20 liters of a solution that is 40% water? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #201960 by </B><A HREF=/tutors/aboutme.mpl?userid=oberobic><B>oberobic(2304)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oberobic><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=201960\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> With 'solution' problems, you have to keep track of how much pure stuff you need.<BR>\n" );
document.write( "This question is tricky because the question presents the complementary percentages.<BR>\n" );
document.write( "Solution 1 is 70% water, so it is 30% pure acetic acid.  We normally call that a 30% solution.<BR>\n" );
document.write( "Solution 2 is 30% water, so it is 70% pure acetic acid.  We normally call that a 70% solution.<BR>\n" );
document.write( "The goal is 20 liters of a 60% acetic acid solution. <BR>\n" );
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document.write( "x = volume of 30% solution<BR>\n" );
document.write( "20 - x = volume of 70% solution<BR>\n" );
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document.write( ".3x = amount of pure acetic acid <BR>\n" );
document.write( ".7(20-x) = the other amount of pure acetic acid.<BR>\n" );
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document.write( "20 liters of 60% acetic acid will have .6*20 = 12 liters of pure acetic acid.<BR>\n" );
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document.write( ".3x + .7(20-x) = 12<BR>\n" );
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document.write( ".3x + 14 - .7x = 12<BR>\n" );
document.write( "-.4x = -2<BR>\n" );
document.write( "x = -2/-.4 = 5 liters of 30% solution<BR>\n" );
document.write( "which means there is<BR>\n" );
document.write( "15 liters of 70% solution.<BR>\n" );
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document.write( "checking to see if we have 12 L of pure acetic acid<BR>\n" );
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document.write( ".3*5  + .7*15 = 1.5 + 10.5 = 12<BR>\n" );
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document.write( "So, 5 liters of 30% acetic acid + 15 liters of 70% acetic acid results in 20 liters of 60% acetic acid solution.<BR>\n" );
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document.write( "Reviewing the question, we need to give the complementary answer in terms of percentage of water.<BR>\n" );
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document.write( "Answer:<BR>\n" );
document.write( "5 liters of 70% water + 15 liters of 30% water = 20 liters of 40% water </SPAN>\n" );
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