document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1184009>Question 1184009</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many quarts of pure antifreeze must be added to 5 quarts of a 30% antifreeze solution to obtain a 50% 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 #814537 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=814537\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "A classic formal algebraic solution would go something like this....<br><BR>\n" );
document.write( "You are mixing 5 quarts that is 30% antifreeze and x quarts that are 100% antifreeze to get (5+x) quarts that is 50% antifreeze:<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.30%285%29%2B1.00%28x%29=.50%285%2Bx%29 ALIGN=MIDDLE  ALT=\".30%285%29%2B1.00%28x%29=.50%285%2Bx%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1.5%2Bx=2.5%2B.5x ALIGN=MIDDLE  ALT=\"1.5%2Bx=2.5%2B.5x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=.5x=1 ALIGN=MIDDLE  ALT=\".5x=1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1%2F.5=2 ALIGN=MIDDLE  ALT=\"x=1%2F.5=2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "ANSWER: 2 quarts<br><BR>\n" );
document.write( "An informal method that will give you the answer within 15 seconds if you understand it....<br><BR>\n" );
document.write( "(1) Look at the three percentages 30, 50, and 100 on a number line and observe/calculate that 50 is 2/7 of the way from 30 to 100.  (30 to 100 is a difference of 70; 30 to 50 is a difference of 20; 20/70 = 2/7.)<BR>\n" );
document.write( "(2)That means 2/7 of the mixture is the 100% antifreeze that you are adding.<BR>\n" );
document.write( "(3) So the 5 quarts you started with is 5/7 of the mixture; that means 2/7 of the mixture is 2 quarts.<br><BR>\n" );
document.write( "ANSWER: 2 quarts<br><BR>\n" );
document.write( " </SPAN>\n" );
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