document.write( "Question 1199320: Bài 7/557) A food producer uses two processing plants, P1 and P2, that
\n" ); document.write( "operate 7 days a week. After processing, beef is graded into high-, mediumand low-quality foodstuf s. High-quality beef is sold to butchers, mediumquality beef is used in supermarket ready-meals and the low-quality beef is
\n" ); document.write( "used in dog food. The producer has contracted to provide 120 kg of high-,
\n" ); document.write( "80 kg of medium- and 240 kg of low-quality beef each week. It costs $4000
\n" ); document.write( "per day to run plant P1 and $3200 per day to run plant P2. Each day P1
\n" ); document.write( "processes 60 kg of high-quality beef, 20 kg of medium-quality beef and 40kg of low-quality beef. The corresponding quantities for P2 are 20 kg, 20 kg
\n" ); document.write( "and 120 kg, respectively. How many days each week should the plants be
\n" ); document.write( "operated to fulfi l the beef contract most economically?
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Algebra.Com's Answer #833149 by ikleyn(52800)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "A food producer uses two processing plants, P1 and P2, that
\n" ); document.write( "operate 7 days a week. After processing, beef is graded into high-, medium and low-quality food stuf s.
\n" ); document.write( "High-quality beef is sold to butchers, medium quality beef is used in supermarket, ready-meals and the low-quality beef
\n" ); document.write( "is used in dog food.
\n" ); document.write( "The producer has contracted to provide 120 kg of high-, 80 kg of medium- and 240 kg of low-quality beef each week.
\n" ); document.write( "It costs $4000 per day to run plant P1 and $3200 per day to run plant P2.
\n" ); document.write( "Each day P1 processes 60 kg of high-quality beef, 20 kg of medium-quality beef and 40kg of low-quality beef.
\n" ); document.write( "The corresponding quantities for P2 are 20 kg, 20 kg and 120 kg, respectively.
\n" ); document.write( "How many days each week should the plants be operated to fulfil the beef contract most economically?
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document.write( "x = days for plant P1;\r\n" );
document.write( "y = days for plant P2.\r\n" );
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document.write( "Objective function to minimize is\r\n" );
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document.write( "    p(x,y) = 4000x + 3200y  dollars.\r\n" );
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document.write( "Constraints\r\n" );
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document.write( "    60x + 20y >= 120   (high-quality beef, in kilograms)\r\n" );
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document.write( "    20x + 20y >=  80   (medium-quality beef)\r\n" );
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document.write( "    40x + 120y >= 240  (low-quality beef)\r\n" );
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document.write( "     0 <= x <= 7;  0<= y <= 7   (days to work)\r\n" );
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document.write( "    \r\n" );
document.write( "Now go to the site  https://www.zweigmedia.com/RealWorld/simplex.html\r\n" );
document.write( "and use the free of charge solver there.\r\n" );
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document.write( "The input to the solver is shown/presented/documented below :\r\n" );
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document.write( "Minimize p = 4000x + 3200y\r\n" );
document.write( "60x + 20y >= 120 \r\n" );
document.write( "20x + 20y >=  80\r\n" );
document.write( "40x + 120y >= 240\r\n" );
document.write( "x >= 0\r\n" );
document.write( "x <= 7\r\n" );
document.write( "y >= 0\r\n" );
document.write( "y <= 7\r\n" );
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document.write( "Copy-paste it to the solver.\r\n" );
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document.write( "It will solve this minimization problem using the Linear Programming method / (the \"simplex method\").\r\n" );
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document.write( "The solver produces this solution (this answer)\r\n" );
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document.write( "   x = 1 day;  y = 3 days;  p = $13600.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "At this point,  the solution is complete.\r
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\n" ); document.write( "\n" ); document.write( "There are several ways to solve the problem.\r
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\n" ); document.write( "\n" ); document.write( "For example, since the problem is  2D  (for  2  unknown variables),  graphics method does work.\r
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\n" ); document.write( "\n" ); document.write( "On solving using graphics method,  see the lesson\r
\n" ); document.write( "\n" ); document.write( "    - Solving minimax problems by the Linear Programming method \r
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