document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=83526>Question 83526</A>: <I><SPAN STYLE=\"word-break: break-all;\">  Adjusting Antifreeze. Angela needs 20 quarts of 50% antifreeze solution in her radiator. She plans to obtain this by mixing some pure antifreeze with and appropriate amount of a 40% solution. How many quarts of each should she use?\r<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 #60050 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=60050\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=amount of 40% antifreeze needed<BR>\n" );
document.write( "Then 20-x=amount of pure antifreeze needed\r<BR>\n" );
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document.write( "Now we know that the amount of pure antifreeze in the 40% solution (0.40x) plus the amount of pure antifreeze (20-x) must equal the amount of pure antifreeze in the final mixture 0.50(20).  So our equation to solve is:\r<BR>\n" );
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document.write( "0.40x+(20-x)=0.50(20)  get rid of parens\r<BR>\n" );
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document.write( "0.40x+20-x=10  subtract 20 from both sides\r<BR>\n" );
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document.write( "0.40x+20-20-x=10-20  collect like terms\r<BR>\n" );
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document.write( "-0.60x=-10  divide both sides by -0.60\r<BR>\n" );
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document.write( "x=16.666 gal --------------------------amount of 40% antifreeze\r<BR>\n" );
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document.write( "20-x=20-16.666=3.333 gal-------------------amount of pure antifreeze\r<BR>\n" );
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document.write( "CK<BR>\n" );
document.write( "3.333+0.40(16.666)=0.50(20)<BR>\n" );
document.write( "3.333+6.664=10<BR>\n" );
document.write( "10=10\r<BR>\n" );
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document.write( "Hope this helps---ptaylor\r<BR>\n" );
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