document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=164965>Question 164965</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0028253264/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Weighted Averages.\r<BR>\n" );
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document.write( "A car radiator has a capacity of 14 quarts and is filled with a 20% antifreeze solution. How much must be drained off and replaced with pure antifreeze to obtain a 40% antifreeze solution? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #121584 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=121584\">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 (0.20(14-x)) plus the amount of pure antifreeze added(x) has to equal the amount of pure antifreeze in the final mixture (0.40(14)).  So, our equation to solve is:\r<BR>\n" );
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document.write( "0.20(14-x) + x=0.40*14  get rid of parens (distributive)<BR>\n" );
document.write( "2.8-0.20x+x=5.6  subtract 2.8 from each side<BR>\n" );
document.write( "2.8 - 2.8-0.20x+x=5.6-2.8 collect like terms\r<BR>\n" );
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document.write( "0.80x=2.8  divide each side by 0.80<BR>\n" );
document.write( "x=3.5 qts-----------------------------------ans<BR>\n" );
document.write( "CK<BR>\n" );
document.write( "0.20*10.5+3.5=5.6<BR>\n" );
document.write( "2.1+3.5=5.6<BR>\n" );
document.write( "5.6=5.6\r<BR>\n" );
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document.write( "Hope this helps---ptaylor\r<BR>\n" );
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