a) $$1-\frac{5}{9} = \frac{9}{9} - \frac{5}{9} = \frac{4}{9}$$
б) $$5\frac{4}{5} - 1\frac{4}{5} = 4\frac{4-4}{5} = 4$$
г) $$6\frac{7}{15} - 3\frac{9}{10} = 6\frac{14}{30} - 3\frac{27}{30} = 5\frac{44}{30} - 3\frac{27}{30} = 2\frac{17}{30}$$
e) $$4\frac{1}{26} - 3\frac{8}{39} = 4\frac{3}{78} - 3\frac{16}{78} = 3\frac{81}{78} - 3\frac{16}{78} = \frac{65}{78} = \frac{5}{6}$$
Ответ: a) $$\frac{4}{9}$$; б) $$4$$; г) $$2\frac{17}{30}$$; e) $$\frac{5}{6}$$