59 Найдите разность: a) 7\frac{3}{5} - 1\frac{2}{5}; б) 28\frac{6}{13} - 7\frac{1}{13}; в) 6 - \frac{2}{5}; г) 21 - \frac{5}{9}; д) 4\frac{1}{7} - 1\frac{4}{7}; ж) 4\frac{1}{2} - 3\frac{1}{4}; e) 12\frac{2}{5} - 1\frac{4}{5}; з) 5\frac{1}{7} - 3\frac{20}{21}.

a) 7\frac{3}{5} - 1\frac{2}{5} = (7 - 1) + (\frac{3}{5} - \frac{2}{5}) = 6 + \frac{1}{5} = 6\frac{1}{5} б) 28\frac{6}{13} - 7\frac{1}{13} = (28 - 7) + (\frac{6}{13} - \frac{1}{13}) = 21 + \frac{5}{13} = 21\frac{5}{13} в) 6 - \frac{2}{5} = 5 + 1 - \frac{2}{5} = 5 + \frac{5}{5} - \frac{2}{5} = 5 + \frac{3}{5} = 5\frac{3}{5} г) 21 - \frac{5}{9} = 20 + 1 - \frac{5}{9} = 20 + \frac{9}{9} - \frac{5}{9} = 20 + \frac{4}{9} = 20\frac{4}{9} д) 4\frac{1}{7} - 1\frac{4}{7} = 4 + \frac{1}{7} - 1 - \frac{4}{7} = 3 + \frac{1}{7} - \frac{4}{7} = 3 - \frac{3}{7} = 2 + \frac{7}{7} - \frac{3}{7} = 2 + \frac{4}{7} = 2\frac{4}{7} ж) 4\frac{1}{2} - 3\frac{1}{4} = 4 + \frac{1}{2} - 3 - \frac{1}{4} = 1 + \frac{1}{2} - \frac{1}{4} = 1 + \frac{2}{4} - \frac{1}{4} = 1 + \frac{1}{4} = 1\frac{1}{4} e) 12\frac{2}{5} - 1\frac{4}{5} = 12 + \frac{2}{5} - 1 - \frac{4}{5} = 11 + \frac{2}{5} - \frac{4}{5} = 11 - \frac{2}{5} = 10 + \frac{5}{5} - \frac{2}{5} = 10 + \frac{3}{5} = 10\frac{3}{5} з) 5\frac{1}{7} - 3\frac{20}{21} = 5 + \frac{1}{7} - 3 - \frac{20}{21} = 2 + \frac{3}{21} - \frac{20}{21} = 2 - \frac{17}{21} = 1 + \frac{21}{21} - \frac{17}{21} = 1 + \frac{4}{21} = 1\frac{4}{21}