145. Solving a chemistry problem

45. (3). A portion of the steel weighing 0.5000 g was dissolved in a flask with a capacity of 50.00 ml. In two volumetric flasks with a capacity of 50.00 ml were selected aliquots of 20.00 ml. A solution containing 0.001000 g of Ti was added to one flask. A solution of hydrogen peroxide was placed in both flasks and brought to the mark.
Calculate the mass fraction (%) of titanium in steel, if the following optical densities of Ax = 0.220 and Ax + St = 0.440 were obtained when photometric measuring the solutions.