document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=936125>Question 936125</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Ali has 20 gallons of 20% sulfuric acid solution. How much 100% sulfuric acid solution must add to make a solution that is steady 50% sulfuric acid. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #569707 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=569707\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let y = the number of gallons of 100% acid solution that you have to add to get a 50% acid solution.\r<BR>\n" );
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document.write( "you have 20 gallons of 20% acid solution.\r<BR>\n" );
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document.write( "your equation will be:\r<BR>\n" );
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document.write( ".2 * 20 + y = .5 * (20 + y)\r<BR>\n" );
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document.write( "20 + y is the total amount of gallons of solution that you will have when you are done.\r<BR>\n" );
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document.write( "simplify this equation to get:\r<BR>\n" );
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document.write( "4 + y = 10 + .5 * y\r<BR>\n" );
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document.write( "subtract .5 * y from both sides of this equation and subtract 4 from both sides of this equation to get:\r<BR>\n" );
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document.write( "y - .5 * y = 10 - 4\r<BR>\n" );
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document.write( "simplify to get:\r<BR>\n" );
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document.write( ".5 * y = 6\r<BR>\n" );
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document.write( "divide both sides of this equation by .5 to get:\r<BR>\n" );
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document.write( "y = 12\r<BR>\n" );
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document.write( "you will need 12 gallons of 100% acid solution added to 20 gallons of 20% acid solution to get 32 gallons of 50% acid.\r<BR>\n" );
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document.write( "the number of gallons of pure acid in the new solution will be .2 * 20 + 12 which is equal to 4 + 12 = 16\r<BR>\n" );
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document.write( "16 / 32 = 50%\r<BR>\n" );
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document.write( "numbers look good.\r<BR>\n" );
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document.write( "your solution is that you will need to add 12 gallons of 100% sulfuric acid to 20 gallons of 20% sulfuric acid to make 32 gallons of 50% sulfuric acid.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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