PPMR
     +--------
JRUY | NMNUGUF
      -JRUY
       ====
       PPRJG
      - JRUY
       =====
        RGURU
       -UJPNG
        =====
         UPYUF
        -FQJRR
         =====
          PNNN

base: 10
letters: FGJMNPQRUY
difficulty: intermediate
restrictions: no multiplication