document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=403247>Question 403247</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How much water must be added to 75 ml of a 75% alcohol solution to obtain 45% alcohol solution? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #285169 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=285169\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x be the amount of water to add\r<BR>\n" );
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document.write( "The final amount of liquid will be (75 + x)\r<BR>\n" );
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document.write( "the key thing to realize is that the amount of actual pure acid before adding water is THE SAME as the amount of actual pure acid after adding water - its just that in one case you have less liquid but a stronger solution and in the other case you have more liquid but a weaker solution\r<BR>\n" );
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document.write( "since the amount of pure acid is the same we can say that\r<BR>\n" );
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document.write( "0.75(75) = 0.45(75 + x)\r<BR>\n" );
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document.write( "56.25 = 33.75 + 0.45x\r<BR>\n" );
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document.write( "if a = b, then b = a, so\r<BR>\n" );
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document.write( "33.75 + 0.45x  = 56.25\r<BR>\n" );
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document.write( "0.45x = 22.5\r<BR>\n" );
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document.write( "x = 22.5/0.45\r<BR>\n" );
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document.write( "x = 50 ml </SPAN>\n" );
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