Найди значение выражения:

a) $\frac{1}{2} + \frac{5}{8} = \frac{4}{8} + \frac{5}{8} = \frac{9}{8} = 1\frac{1}{8}$ б) $\frac{3}{4} - \frac{1}{2} = \frac{3}{4} - \frac{2}{4} = \frac{1}{4}$ в) $\frac{7}{10} - \frac{3}{5} = \frac{7}{10} - \frac{6}{10} = \frac{1}{10}$ г) $\frac{5}{7} - \frac{3}{14} = \frac{10}{14} - \frac{3}{14} = \frac{7}{14} = \frac{1}{2}$ д) $\frac{5}{9} - \frac{5}{12} = \frac{20}{36} - \frac{15}{36} = \frac{5}{36}$ е) $\frac{7}{12} - \frac{7}{20} = \frac{35}{60} - \frac{21}{60} = \frac{14}{60} = \frac{7}{30}$ ж) $\frac{5}{6} + \frac{3}{8} = \frac{20}{24} + \frac{9}{24} = \frac{29}{24} = 1\frac{5}{24}$ з) $\frac{19}{21} - \frac{11}{15} = \frac{95}{105} - \frac{77}{105} = \frac{18}{105} = \frac{6}{35}$ и) $\frac{21}{22} - \frac{3}{55} = \frac{105}{110} - \frac{6}{110} = \frac{99}{110} = \frac{9}{10}$ к) $\frac{5}{42} + \frac{10}{63} = \frac{15}{126} + \frac{20}{126} = \frac{35}{126} = \frac{5}{18}$ л) $\frac{11}{21} - \frac{2}{35} = \frac{55}{105} - \frac{6}{105} = \frac{49}{105} = \frac{7}{15}$ м) $\frac{5}{24} + \frac{7}{60} = \frac{25}{120} + \frac{14}{120} = \frac{39}{120} = \frac{13}{40}$