Вариант 1:
1. a) \(\frac{1}{4} + \frac{3}{7} = \frac{7}{28} + \frac{12}{28} = \frac{19}{28}\)
b) \(\frac{6}{1} + \frac{1}{5} = \frac{30}{5} + \frac{1}{5} = \frac{31}{5} = 6\frac{1}{5}\)
2. a) \(\frac{2}{3} + \frac{5}{2} = \frac{4}{6} + \frac{15}{6} = \frac{19}{6} = 3\frac{1}{6}\)
b) \(\frac{3}{9} + \frac{8}{2} = \frac{3}{9} + \frac{36}{9} = \frac{39}{9} = \frac{13}{3} = 4\frac{1}{3}\)