document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=158772>Question 158772</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0131869795/algebrahomeworkh>Begining Algebra: Early Graphing</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> A chemist needs to combine two solutions of a certain acid.  How many liters of a 30% acid solution should be added to 40 liters of a 12% acid solution to obtain a final mixture that is 20% acid? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #117002 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=117002\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=amount of 30% acid solution needed\r<BR>\n" );
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document.write( "Now we know that the amount of pure acid in the 30% solution (0.30x) plus the amount of pure acid in the 40 liters of  12% solution (0.12*40) has to equal the amount of pure acid in the solution after the mixture takes place (0.20(40+x)).  So our equation to solve is:\r<BR>\n" );
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document.write( "0.30x+0.12*40=0.20(40+x)  get rid of parens<BR>\n" );
document.write( "0.30x+4.8=8+0.20x  subtract 4.8 and also 0.20x from both sides<BR>\n" );
document.write( "0.30x-0.20x+4.8-4.8=8-4.8+0.20x-0.20x  collect like terms<BR>\n" );
document.write( "0.10x=3.2  divide each side by 0.10<BR>\n" );
document.write( "x=32 gal------------------------------amount of 30% solution needed\r<BR>\n" );
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document.write( "CK<BR>\n" );
document.write( "0.30*32+0.12*40=0.20*72<BR>\n" );
document.write( "9.6+4.8=14.4<BR>\n" );
document.write( "14.4=14.4\r<BR>\n" );
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document.write( "Hope this helps----ptaylor<BR>\n" );
document.write( " </SPAN>\n" );
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