5

47 : (2 3/4 + 10/19) = 47 : (11/4 + 10/19) = 47 : ((11*19 + 10*4) / (4*19)) = 47 : ((209 + 40) / 76) = 47 : (249/76) = 47 * 76/249 = (47 * 76) / (47 * 5,3) = 76/5,3 = 14,33