document.write( "Question 1140905: Mandie has enough sheets of paper to give each of her friends 3 sheets and has 31
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Algebra.Com's Answer #761451 by ikleyn(52833) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "From the condition, an attentive reader can notice momentarily, that the number of friends is 31-9 = 22.\r\n" );
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document.write( "Then the number of sheets is 4*22 + 9 = 88+9 = 97.      ANSWER\r\n" );
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document.write( "CHECK.  22*3+31 = 66 + 31 = 97, the same number.   ! Correct !\r\n" );
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document.write( "Another, formal algebra solution is to write this system of 2 equations\r\n" );
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document.write( "    X - 3*N = 31,     (1)\r\n" );
document.write( "    X - 4*N =  9,     (2)\r\n" );
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document.write( "where X is the number of sheet and N is the number of friends, and solve it by any way.\r\n" );
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