document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=992498>Question 992498</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Pure acid is to be added to a 10% acid solution to obtain 81 L of a 20% acid solutions. What amounts of each should be used?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #612191 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=612191\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  Pure acid is to be added to a 10% acid solution to obtain 81 L of a 20% acid solutions.<BR>\n" );
document.write( " What amounts of each should be used?<BR>\n" );
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document.write( "let a = amt of pure acid to be used <BR>\n" );
document.write( "then<BR>\n" );
document.write( "(81-a) = amt of 10% solution required<BR>\n" );
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document.write( "A typical mixture equation<BR>\n" );
document.write( "a + .10(81-a) = .20(81)<BR>\n" );
document.write( "a + 8.1 - .10a = 16.2<BR>\n" );
document.write( "a - .1a = 16.2 - 8.1<BR>\n" );
document.write( ".9a = 8.1<BR>\n" );
document.write( "a = 8.1/.9<BR>\n" );
document.write( "a = 9 liters of pure acid<BR>\n" );
document.write( "then<BR>\n" );
document.write( "81- 9 = 72 liters of 10% solution </SPAN>\n" );
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