B239
      +---------
21A59 | 45A8268B
       -48009
        =====
         00606
        -B011B
         =====
         2821A8
        -A35BB9
         ======
          A039BB
         -A0AAAB
          ======
            4518

base: 12
letters: 0123456789AB
difficulty: intermediate
missing: 7