Задача 1: Вычислите:

a) \(\frac{3}{4} + \frac{4}{5}\) = \(\frac{3*5}{4*5} + \frac{4*4}{5*4}\) = \(\frac{15}{20} + \frac{16}{20}\) = \(\frac{31}{20}\) б) \(\frac{2}{3} + \frac{1}{7}\) = \(\frac{2*7}{3*7} + \frac{1*3}{7*3}\) = \(\frac{14}{21} + \frac{3}{21}\) = \(\frac{17}{21}\) в) \(\frac{2}{13} + 0\) = \(\frac{2}{13}\) г) \(\frac{5}{9} + \frac{2}{11}\) = \(\frac{5*11}{9*11} + \frac{2*9}{11*9}\) = \(\frac{55}{99} + \(\frac{18}{99}\) = \(\frac{73}{99}\) д) \(\frac{5}{12} + \frac{3}{4}\) = \(\frac{5}{12} + \frac{3*3}{4*3}\) = \(\frac{5}{12} + \frac{9}{12}\) = \(\frac{14}{12}\) = \(\frac{7}{6}\) е) \(\frac{5}{6} + \frac{7}{8}\) = \(\frac{5*4}{6*4} + \frac{7*3}{8*3}\) = \(\frac{20}{24} + \frac{21}{24}\) = \(\frac{41}{24}\)