Решим пример:
$$7 - 4\frac{4}{5} = 6\frac{5}{5} - 4\frac{4}{5} = (6-4) + (\frac{5}{5} - \frac{4}{5}) = 2 + \frac{1}{5} = 2\frac{1}{5} $$
$$5\frac{4}{13} - 3\frac{9}{13} = (5-3) + (\frac{4}{13} - \frac{9}{13}) = 2 + ( - \frac{5}{13}) = 1 + 1 - \frac{5}{13} = 1 + \frac{13}{13} - \frac{5}{13} = 1 + \frac{8}{13} = 1\frac{8}{13}$$
Ответ: $$2\frac{1}{5}; 1\frac{8}{13}$$