document.write( "Question 669092: i am a number between 20 and 30. i am a prime number. the difference between my digits is 7.
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Algebra.Com's Answer #416069 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "We'll check all the integers between 20 and 30:\r\n" );
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document.write( "21 is not prime because it is divisible by 3 and 7.\r\n" );
document.write( "22 is not prime because it is divisible by 2 and 11.\r\n" );
document.write( "23 is prime but its digits do not differ by 7 because 3-2=1 not 7.\r\n" );
document.write( "24 is not prime because it is divisible by 2,3,4,6,8 and 12.\r\n" );
document.write( "25 is not prime because it is divisible by 5.\r\n" );
document.write( "26 is not prime because it is divisible by 2 and 13.\r\n" );
document.write( "27 is not prime because it is divisible by 3 and 9.\r\n" );
document.write( "28 is not prime because it is divisible by 2,7, and 14.\r\n" );
document.write( "29 is prime and its digits DO differ by 7 since 9-2=7.\r\n" );
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document.write( "So that's it!  29\r\n" );
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document.write( "Edwin
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