document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=789692>Question 789692</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many pounds of a chicken feed that sells for $5 a lb. must be mixed with 400 pounds of a feed<BR>\n" );
document.write( "that sells for $8 a lb.to make a chicken feed that sells for $7.50 a lb.? 5x+8x/400=7.50 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #478904 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=478904\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Pay closer attention to cost and pounds.  This is a mixture problem and the concentration is DOLLARS per POUND.  Your target is 7.50 dollars per pound.\r<BR>\n" );
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document.write( "Using the variable choices as you tried,<BR>\n" );
document.write( "x = pounds of the lower priced feed<BR>\n" );
document.write( "y = pounds of the higher priced feed, but you do NOT need this as variable.\r<BR>\n" );
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document.write( "Already you were given to start with 400 pounds of the 8$/pound feed.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28%285x%2B8%2A400%29%2F%28x%2B400%29=7.50%29 ALIGN=MIDDLE  ALT=\"highlight%28%285x%2B8%2A400%29%2F%28x%2B400%29=7.50%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "SOLVE FOR x.\r<BR>\n" );
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document.write( "SOME INSTRUCTION---------------------------------------------\r<BR>\n" );
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document.write( "DEVELOP THE EQUATION:\r<BR>\n" );
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document.write( "{COST OF MIXTURE}/{AMOUNT OF MIXTURE}={PRICE FOR MIXTURE}\r<BR>\n" );
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document.write( "You know the amount of the $8/pound chicken feed, 400 pounds.<BR>\n" );
document.write( "The amount of the $5/pound feed is unknown variable, x.<BR>\n" );
document.write( "Cost for the mixture is 5x+8*400 dollars.\r<BR>\n" );
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document.write( "The amount of mixture is a variable expression, x+400.\r<BR>\n" );
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document.write( "You want the PRICE of the mixture to be 7.50 dollars per pound.\r<BR>\n" );
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document.write( "Put this altogether and make <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%285x%2B8%2A400%29%2F%28x%2B400%29=7.50 ALIGN=MIDDLE  ALT=\"%285x%2B8%2A400%29%2F%28x%2B400%29=7.50\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "You clear the \"fraction\" by doing something to BOTH sides of the equation.  This means, multiply left and right sides by (x+400); simplify if you wish.  You are initially relying on the idea, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n%2Fd=c ALIGN=MIDDLE  ALT=\"n%2Fd=c\"   DISABLED_style= \"max-width:90%; height:auto;\" > being equivalent to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28n%2Fd%29%28d%29=cd ALIGN=MIDDLE  ALT=\"%28n%2Fd%29%28d%29=cd\"   DISABLED_style= \"max-width:90%; height:auto;\" >, which would be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n=cd ALIGN=MIDDLE  ALT=\"n=cd\"   DISABLED_style= \"max-width:90%; height:auto;\" >.   (Generalizing here so you see the rule).  \r<BR>\n" );
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