



 
Hi Denise, Since all 4 digits must be odd, then the number cannot be in the range of 2000  2999. So we know that the number must begin with a 3. Since 0 is not an odd number the so the digits cannot be 0. So we know than the number is truly between 3111  3159. The odd digits are 1, 3, 5, 7, 9, which ones have a difference of 6 that have not been used? Hope this helps, Janice  


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