document.write( "Question 1139187: A farmer bought a number of pigs for $200. However, 4 of them died before he could sell the rest at a profit of 7 per pig. His total profit was $72. How many pigs did he originally buy?
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Algebra.Com's Answer #756967 by ikleyn(52788) $\"\"$ $\"About$

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document.write( "Let n = # of pigs originally bought.\r\n" );
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document.write( "Then you have this equation from the condition\r\n" );
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document.write( "     -  = 7,   or\r\n" );
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document.write( "     -  = 7.\r\n" );
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document.write( "Multiply both sides by n*(n-4), simplify and solve for n\r\n" );
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document.write( "    272n - 200*(n-4) = 7n*(n-4)\r\n" );
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document.write( "    72n + 800 = 7n^2 - 28n\r\n" );
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document.write( "    7n^2 - 100n - 800 = 0\r\n" );
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document.write( "    n =  = .\r\n" );
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document.write( "The solution to the problem is the positive integer  n =  =  = 20.\r\n" );
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document.write( "ANSWER.  There were 20 pigs originally.\r\n" );
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document.write( "CHECK.     -  = 17 - 10 = 7  dollars  profit for each of 16 sold pigs.   ! Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "To see many other similar solved problems, look into the lessons\r
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