document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=166168>Question 166168</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many milliliters of pure acid must be added to 100 milliliters of a 10% acid solution to obtain a 20% solution? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #122485 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=122485\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=amount of pure acid needed\r<BR>\n" );
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document.write( "Now we know that the amount of pure acid added (x) plus the amount of pure acid in the 100 ml solution (0.10*100) has to equal the amount of pure acid in the final solution (0.20(100+x)).  So our equation to solve is:\r<BR>\n" );
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document.write( "x+0.10*100=0.20(100+x)  get rid of parens (distributive law) and simplify<BR>\n" );
document.write( "x+10=20+0.20x  subtract 0.20x and also 10 from each side<BR>\n" );
document.write( "x+10-10-0.20x=20-10+0.20x-0.20x  collect like terms\r<BR>\n" );
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document.write( "0.80x=10  divide each side by 0.80<BR>\n" );
document.write( "x=12.5 ml-----------------amount of pure acid needed\r<BR>\n" );
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document.write( "CK<BR>\n" );
document.write( "12.5+10=0.20(100+12.5)=0.20(112.5)<BR>\n" );
document.write( "22.5=22.5\r<BR>\n" );
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document.write( "Hope this helps----ptaylor<BR>\n" );
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