document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=751428>Question 751428</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A radiator contains 3 gallons of 40% antifreeze solution. How many gallons of pure antifreeze must be added to obtain 50% solution? Please Help!!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #457193 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=457193\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are 3*0.4 = 1.2 gallons of pure antifreeze.\r<BR>\n" );
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document.write( "Let x = amount (in gallons) of pure antifreeze needed to add\r<BR>\n" );
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document.write( "If you add x gallons of pure antifreeze to 1.2 gallons of pure antifreeze, you'll have 1.2+x gallons of pure antifreeze\r<BR>\n" );
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document.write( "You are also adding x gallons of pure antifreeze to the 3 gallons of solution already there, so the total amount of solution is now 3+x gallons.\r<BR>\n" );
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document.write( "We can now say this\r<BR>\n" );
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document.write( "(1.2+x)/(3+x) = 0.5\r<BR>\n" );
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document.write( "since we want the percentage of pure antifreeze to total solution must be 50%\r<BR>\n" );
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document.write( "Now solve for x\r<BR>\n" );
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document.write( "(1.2+x)/(3+x) = 0.5\r<BR>\n" );
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document.write( "1.2+x = 0.5(3+x)\r<BR>\n" );
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document.write( "1.2+x = 1.5+0.5x\r<BR>\n" );
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document.write( "x = 1.5+0.5x-1.2\r<BR>\n" );
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document.write( "x-0.5x = 1.5-1.2\r<BR>\n" );
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document.write( "0.5x = 0.3\r<BR>\n" );
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document.write( "x = 0.3/0.5\r<BR>\n" );
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document.write( "x = 0.6\r<BR>\n" );
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document.write( "So you need to add <font color=\"red\">0.6 gallons</font> of pure antifreeze to obtain 50% solution. </SPAN>\n" );
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