document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=128656>Question 128656</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help solving this problem. Please help. <BR>\n" );
document.write( "You need a 21% salt solution to fill your fish tank. How much of the 15% salt solution should be added to 12 gallons of the 25% salt solution to create the desired salt solution? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #94152 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=94152\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=amount of 15% solution needed\r<BR>\n" );
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document.write( "Total solution after the mixture takes place is 12+x gal, right?\r<BR>\n" );
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document.write( "Now we know that the amount of pure salt in the 15% solution(0.15x) plus the amount of pure salt in the 12 gal (0.25*12) has to equal the amount of pure salt in the final mixture (0.21*(12+x)).  So our equation to solve is:\r<BR>\n" );
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document.write( "0.15x+0.25*12=0.21(12+x)   get rid of parens and simplify\r<BR>\n" );
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document.write( "0.15x+3=2.52+0.21x  subtract 0.15x and also 2.52 from both sides\r<BR>\n" );
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document.write( "0.15x-0.15x+3-2.52=2.52-2.52+0.21x-0.15x  collect like terms\r<BR>\n" );
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document.write( "0.48=0.06x  divide both sides by 0.06\r<BR>\n" );
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document.write( "x=8 gal--------------- amount of 15% solution needed\r<BR>\n" );
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document.write( "CK\r<BR>\n" );
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document.write( "0.15*8+0.25*12=0.21*20<BR>\n" );
document.write( "1.2+3=4.2<BR>\n" );
document.write( "4.2=4.2\r<BR>\n" );
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document.write( "Hope this helps----ptaylor\r<BR>\n" );
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document.write( " </SPAN>\n" );
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