1. Выполните действия:
a) $$\frac{16}{19}-\frac{11}{19}+\frac{4}{19} = \frac{16-11+4}{19} = \frac{9}{19}$$
Ответ: $$\frac{9}{19}$$
б) $$6\frac{5}{13}+2\frac{9}{13} = (6+2) + (\frac{5}{13}+\frac{9}{13}) = 8 + \frac{14}{13} = 8 + 1\frac{1}{13} = 9\frac{1}{13}$$
Ответ: $$9\frac{1}{13}$$
в) $$5-3\frac{6}{7} = 4\frac{7}{7}-3\frac{6}{7} = (4-3) + (\frac{7}{7}-\frac{6}{7}) = 1+\frac{1}{7} = 1\frac{1}{7}$$
Ответ: $$1\frac{1}{7}$$
г) $$7\frac{2}{9}-3\frac{4}{9} = 6\frac{11}{9}-3\frac{4}{9} = (6-3) + (\frac{11}{9}-\frac{4}{9}) = 3 + \frac{7}{9} = 3\frac{7}{9}$$
Ответ: $$3\frac{7}{9}$$