number theory

 

Modify one digit in the number 31743 can make it a multiple of 281.  What is the number after change     

 

31743 / 281  =  112.96+     Truncate the .96 ... all we want right now is the 112.     

 

112 x 281  =  Ruh Roh, this isn't going to work, so try 111.     

 

111 x 281  =  31753     Bingo.  Change the 4 to a 5.     

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