A 20 mL solution of hydrogen peroxide reacts quantitatively with a 20 mL solution of KMnO4 acidified with dilute H2SO4. The same volume of the KMnO4 solution is decolourized by 10 mL of MnSO4 in neutral medium simultaneously forming a dark brown precipitate of hydrated MnO2. The brown precipitate is dissolved in 20 mL of 0.2 M sodium oxalate under boiling condition in the presence of dilute H2SO4. Calculate the volume strength of H2O2.