document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=165519>Question 165519</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A tank contains 50 gallons of a 40% solution of anti-freeze. How much solution needs to be drained out and replaced with pure anti-freeze to obtain a 50% solution? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #122011 by </B><A HREF=/tutors/aboutme.mpl?userid=Mathtut><B>Mathtut(3670)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Mathtut><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=122011\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=amount that needs to be drained off and replaced with pure antifreeze<BR>\n" );
document.write( "Now we know that the amount of pure antifreeze left after x amount is drained off (0.4(50-x)) plus the amount of pure antifreeze added(x) has to equal the amount of pure antifreeze in the final mixture (0.5(50)). So, our equation to solve is: <BR>\n" );
document.write( "0.4(50-x) + x=0.50*50 get rid of parenthesis(distributive)<BR>\n" );
document.write( "20-.4x+x=25 subtract 20 from each side<BR>\n" );
document.write( "and combine like terms <BR>\n" );
document.write( ".6x=5 divide each side by 0.6<BR>\n" );
document.write( "x=8.33 qts-----------------------------------ans<BR>\n" );
document.write( "CK<BR>\n" );
document.write( ".4(50-8.33)+8.33=25<BR>\n" );
document.write( "  (50/3)+25/3=25<BR>\n" );
document.write( "       75/3=25<BR>\n" );
document.write( "        25=25<BR>\n" );
document.write( "Hope this helps </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );