Solution: The Abbot's Puzzle

The code...

local
   proc {Abbot X}
      M={FD.decl} 
      W={FD.decl} 
      C={FD.decl}
      
   in
      X = [M W C]
      M + W + C =: 100
      M * 6 + W * 4 + C =: 200
      M * 5 =: W    % additional condition added by Dudeney      
      {FD.distribute split X}
   end
   
in
   {ExploreAll Abbot}
end

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