D U V O + U O V D = 4987 logically D + U = 4; U + O = 9; V + V = 8; O + D = 7; V = 4 because 2V = 8; D or U = 1 or 3; U or O = 6 or 8; O or D = 4 or 6; D cannot = 3, because U = 1; O would equal 8 which is above 7; D = 1; U = 3; O = 6; 3 + U = 9; V = 4;