1) if nP5=6720 find n
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document.write( "Those 5 factors on the left average to the middle one n-2, \r\n" );
document.write( "so the left side isn't far from
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document.write( "So the solution to\r\n" );
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document.write( "should be close to the correct answer,\r\n" );
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document.write( "So we try 8\r\n" );
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document.write( "n = 8\r\n" );
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document.write( "2) solve equation for n
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document.write( " nP3=210
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document.write( "These 3 factors on the left average to the middle one n-1, \r\n" );
document.write( "so the left side isn't far from
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document.write( "So the solution to\r\n" );
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document.write( "should be close to the correct answer,\r\n" );
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document.write( "So we try 7\r\n" );
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document.write( "n = 7\r\n" );
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document.write( "Edwin
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