document.write( "Question 713915: A cheese manufacturer combines Romano cheese that costs $4.00 per pound with aged Parmesan cheese which costs $7.00 per pound to make 30 lbs of a grated cheese mixture. How many pounds of each cheese should they include if they want the 30 ound mixture to cost $5.70 per pound? \n" ); document.write( "
Algebra.Com's Answer #438615 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
The manufacturer wants to mix some high strength cheese with so low strength cheese and have a known quantity of mixture of a known intermediate strength cheese. Strength here is money, price (some expected dollars per pound).\r
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\n" ); document.write( "\n" ); document.write( "M=pounds of mixture, 30 pounds.
\n" ); document.write( "u= amount of low strength, unknown pounds
\n" ); document.write( "v= amount of high strength cheese, unknown pounds
\n" ); document.write( "L = strength of the low strength cheese, $4/pound
\n" ); document.write( "H = high strength cheese, $7/pound
\n" ); document.write( "T = Target price per pound 5.70\r
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\n" ); document.write( "\n" ); document.write( "Setup Equations.
\n" ); document.write( "\"%28Lu%2BHv%29%2FM=T\"
\n" ); document.write( "\"u%2Bv=M\"\r
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\n" ); document.write( "\n" ); document.write( "Solve for u and v.
\n" ); document.write( "Sometimes the values given are conveniently chosen to make the solving easy, but you don't want to always rely on that.
\n" ); document.write( "\"Lu%2BHv=TM\"
\n" ); document.write( "and
\n" ); document.write( "\"u%2Bv=M\"
\n" ); document.write( "How neat those numbers will be, we not know (unless we substitute them NOW).
\n" ); document.write( "v=M-u, so keep going in symbols, subsituting this one into the percents equation:
\n" ); document.write( "\"Lu%2BH%28M-u%29=TM\"
\n" ); document.write( "\"Lu%2BHM-Hu=TM\"
\n" ); document.write( "\"%28L-H%29u%2BHM=TM\"
\n" ); document.write( "\"%28L-H%29u=TM-HM\"
\n" ); document.write( "\"%28L-H%29u=M%28T-H%29\"
\n" ); document.write( "\"u=M%28T-H%29%2F%28L-H%29\"\r
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\n" ); document.write( "\n" ); document.write( "Might be most convenient if done symbolically to use
\n" ); document.write( "\"highlight%28u=M%28H-T%29%2F%28H-L%29%29\", which was multiplied by \"%28-1%29%2F%28-1%29\"
\n" ); document.write( "and
\n" ); document.write( "\"highlight%28v=M-u%29\", since you just found u.\r
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\n" ); document.write( "\n" ); document.write( "Substitute Values to determine values of u and v.
\n" ); document.write( "\"u=%28M%287-5.7%29%29%2F%287-4%29\", which you compute and then find the value for v.
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