document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=758597>Question 758597</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A 50% acid solution is mixed with a 25% acid solution to form a 40% acid solution. How many liters of the 25% acid solution are used to make 20 liters of the 40% acid solution? \r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "\"50x +25(20-x)=40\" seems to be wrong. Help me please!  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #461592 by </B><A HREF=/tutors/aboutme.mpl?userid=John10><B>John10(297)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=John10><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=John10><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=461592\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hi,\r<BR>\n" );
document.write( "\n" );
document.write( "You have some good idea :)\r<BR>\n" );
document.write( "\n" );
document.write( "For this problem,\r<BR>\n" );
document.write( "\n" );
document.write( "You need to find 2 equations for a linear system.\r<BR>\n" );
document.write( "\n" );
document.write( "Let call x to be the amount of 50% acid and y to be the amount of 25% acid\r<BR>\n" );
document.write( "\n" );
document.write( "We know the total is 20 L, thus the first equation is x + y = 20\r<BR>\n" );
document.write( "\n" );
document.write( "Another equation would be about the mixture: 0.5x + 0.25y = 0.4(20) = 8\r<BR>\n" );
document.write( "\n" );
document.write( "So you have the system of 2 linear equations:\r<BR>\n" );
document.write( "\n" );
document.write( "x + y = 20<BR>\n" );
document.write( "0.5x + 0.25y = 8\r<BR>\n" );
document.write( "\n" );
document.write( "You can solve for x and y ( which is the amount of 25% acid)\r<BR>\n" );
document.write( "\n" );
document.write( "If you need some more assistance, please email me.\r<BR>\n" );
document.write( "\n" );
document.write( "Thank you! </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );