document.write( "Question 1154580: Hi\r
\n" ); document.write( "\n" ); document.write( "A bookstore owner bought x pencils for 32 dollars and sold them at a profit of 5 cents per pencil. She ended up with 20 pencils left and received 35 dollars for the sale of the pencils.\r
\n" ); document.write( "\n" ); document.write( "How many pencils did he buy.\r
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Algebra.Com's Answer #777036 by ikleyn(52791) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "Let n be the number of pencils under the problem's question.\r\n" );
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document.write( "The the owner bought n pencils for 32 dollars at the price    cents per dollar.\r\n" );
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document.write( "Then the owner sold (n-20) pencils for 35 dollars, at the price    cents per pencil.\r\n" );
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document.write( "The difference in prices per pencil was 5 cents, according to the condition.\r\n" );
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document.write( "It gives you an equation\r\n" );
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document.write( "     -  = 5  cents.\r\n" );
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document.write( "It is your basic equation to solve and to find the unknown \"n\".\r\n" );
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document.write( "Cancel the factor 5 in both sides\r\n" );
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document.write( "     -  = 1.     (*)\r\n" );
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document.write( "To solve this equation, multiply both sides by n*(n-20) and reduce the equation to standard quadratic equation form;\r\n" );
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document.write( "then solve it by any method you know / (by any method you can).\r\n" );
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document.write( "ANSWER.  n= 160.\r\n" );
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document.write( "CHECK.  I will check equation (*):   -  = 5 - 4 = 1.    ! Precisely correct !\r\n" );
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