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 #138239 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=138239\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How many liters of a 30% alcohol solution must be mixed with 80 liters<BR>\n" );
document.write( " of a 80% solution to get a 40% solution. <BR>\n" );
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document.write( "I would do it this way:<BR>\n" );
document.write( "Let x = amt of 30% solution:<BR>\n" );
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document.write( "Then when the two solutions are mixed together:<BR>\n" );
document.write( "(x+80) = amt of 40% solution<BR>\n" );
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document.write( "a mixture equation using decimal equiv of per cent<BR>\n" );
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document.write( "30% amt + 80% amt = 40% amt<BR>\n" );
document.write( ".3x + .8(80) = .4(x+80)<BR>\n" );
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document.write( ".3x + 64 = .4x + 32<BR>\n" );
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document.write( ".3x -.4x = 32 - 64<BR>\n" );
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document.write( "-.1x = -32<BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-32%29%2F%28-.1%29 ALIGN=MIDDLE  ALT=\"%28-32%29%2F%28-.1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = +320 liters of 30 % solution required </SPAN>\n" );
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