document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=657343>Question 657343</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Juice-O-Rama is a refreshment stand specializing in a fruit drink mixture of orange juice and prune juice. The orange juice costs $1.20 per liter and the prune juice costs $1.40 per liter. If they need 8 liters of the final drink at a cost of $1.24 per liter, how many liters of each juice will they need to make their specialty drink?\r<BR>\n" );
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document.write( "I don't really know how to start, but I put x as the liters of orange juice and y as the liters of prune juice. I set x+y=8, but this is where I get confused </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #409841 by </B><A HREF=/tutors/aboutme.mpl?userid=kevwill><B>kevwill(135)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=kevwill><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=kevwill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=409841\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You're off to a good start.  \r<BR>\n" );
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document.write( "Let x = liters of orange juice<BR>\n" );
document.write( "and y = liters of prune juice.\r<BR>\n" );
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document.write( "Then x + y = 8.\r<BR>\n" );
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document.write( "Since each liter of orange juice costs $1.20 and each liter of prune juice costs $1.40, the total cost of the mixture is 1.20x + 1.40y.\r<BR>\n" );
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document.write( "We are given that the final drink costs $1.24 per liter, or $1.24*8 = $9.92 for the entire 8 liters.  This gives us our second equation:\r<BR>\n" );
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document.write( "1.20x + 1.40y = 9.92\r<BR>\n" );
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document.write( "We now have two equations in two unknowns:\r<BR>\n" );
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document.write( "x + y = 8<BR>\n" );
document.write( "1.2x + 1.4y = 9.92\r<BR>\n" );
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document.write( "We'll use substitution.  From the first equation, move x to the right (by subtracting x from each side), giving \r<BR>\n" );
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document.write( "y = 8 - x\r<BR>\n" );
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document.write( "Substituting for y in the second equation gives\r<BR>\n" );
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document.write( "1.2x + 1.4(8-x) = 9.92\r<BR>\n" );
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document.write( "Expanding:\r<BR>\n" );
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document.write( "1.2x + 11.2 - 1.4x = 9.92\r<BR>\n" );
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document.write( "Subtract 11.2 from each side and regroup:\r<BR>\n" );
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document.write( "(1.2x - 1.4x) = 9.92 - 11.2\r<BR>\n" );
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document.write( "Combining terms:\r<BR>\n" );
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document.write( "-0.2x = -1.28\r<BR>\n" );
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document.write( "Dividing both sides by -0.2:\r<BR>\n" );
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document.write( "x = -1.28/-0.2 = 6.4\r<BR>\n" );
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document.write( "From our first substitution, \r<BR>\n" );
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document.write( "y = 8 - 6.4 = 1.6\r<BR>\n" );
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document.write( "So the final drink contains 6.4 liters of orange juice and 1.6 liters of prune juice.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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