document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=184199>Question 184199</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0321319087/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> This is a teacher generated question.\r<BR>\n" );
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document.write( "How many liters of a 30% alcohol solution must be mixed with 80 liters of a 80% solution to get a 40% solution.\r<BR>\n" );
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document.write( "I've tried the following, but I'm not sure it's right at all.  \r<BR>\n" );
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document.write( "a+b=80L<BR>\n" );
document.write( "30a+80b=3200<BR>\n" );
document.write( "Multiply by -30 to use the elimination format, this give you:\r<BR>\n" );
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document.write( "-30a - 30b = -2400L<BR>\n" );
document.write( "30a  + 80b =  3200L\r<BR>\n" );
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document.write( "       50b = 800<BR>\n" );
document.write( "   b=16L, which makes a = 64L \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 #138240 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=138240\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> AT LEAST YOU GAVE IT A TRY BUT I CAN'T FOLLOW WHAT YOU DID BECAUSE I'M NOT SURE WHAT a AND b REPRESENT.  ANYWAY, SEE IF YOU CAN FOLLOW WHAT I DID. NICE TRY!!!!!<BR>\n" );
document.write( "Let x=number of liters of 30% solution needed<BR>\n" );
document.write( "Now we know that the pure alcohol in the 30% solution (0.30x) plus the amount of pure alcohol in the 80% solution (0.80*80) has to equal the amount of pure alcohol in the final mixture (0.40(80+x)), so our equation to solve is:\r<BR>\n" );
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document.write( "0.30x+0.80*80=0.40(80+x) get rid of parens<BR>\n" );
document.write( "0.30x+64=32+0.40x subtract 64 and also 0.40x from each side<BR>\n" );
document.write( "0.30x-0.40x+64-64=32-64+0.40x-0.40x  collect like terms<BR>\n" );
document.write( "-0.10x=-32  divide each side by -0.10<BR>\n" );
document.write( "x=320 liters----------------------ans\r<BR>\n" );
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document.write( "CK<BR>\n" );
document.write( "0.30*320+0.80*80=0.40*400<BR>\n" );
document.write( "96+64=160<BR>\n" );
document.write( "160=160\r<BR>\n" );
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document.write( "Hope this helps---ptaylor </SPAN>\n" );
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