dcowboys107 Posted February 8, 2006 Share Posted February 8, 2006 2 + 1 + 3 + 2 = 8 The number 21328 has a unique feature: The sum of the first four digits equals the units digit. How many EVEN five-digit numbers have this unique property? Link to comment Share on other sites More sharing options...
m4rc Posted February 8, 2006 Share Posted February 8, 2006 There are 34 different numbers that match. 11114 22228 51118,15118,11518,11158 31116,13116,11316,11136 42118 and permutations of the first four digits make 12 more 32218 and permutations of the first four digits make 12 more Link to comment Share on other sites More sharing options...
m4rc Posted February 8, 2006 Share Posted February 8, 2006 forgot 22116 and its permutations. That should bring the total to 40. Link to comment Share on other sites More sharing options...
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