Соедини части \dfrac{11}{13} \cdot \left(\dfrac{5}{11} + \dfrac{11}{33}\right) = \dfrac{8}{11} \cdot \left(\dfrac{4}{5} - \dfrac{1}{4}\right) = \left(\dfrac{1}{2} - \dfrac{1}{8}\right) \cdot \dfrac{2}{3} = \dfrac{2}{5} \dfrac{1}{4} \dfrac{2}{3}