выполните действия. 21$$\frac{4}{5}$$+2$$\frac{3}{5}$$-13$$\frac{1}{5}$$ 2$$\frac{4}{5}$$-1$$\frac{7}{5}$$ 12$$\frac{4}{5}$$+6$$\frac{3}{5}$$

Решим каждое выражение по отдельности:

1. 21$$\frac{4}{5}$$+2$$\frac{3}{5}$$-13$$\frac{1}{5}$$ = (21 + 2 - 13) + ($$\frac{4}{5}$$ +$$\frac{3}{5}$$ - $$\frac{1}{5}$$) = 10 + $$\frac{6}{5}$$ = 10 + 1$$\frac{1}{5}$$ = 11$$\frac{1}{5}$$
2. 2$$\frac{4}{5}$$-1$$\frac{7}{5}$$ = 2$$\frac{4}{5}$$-$$\frac{12}{5}$$ = $$\frac{14}{5}$$ -$$\frac{12}{5}$$ = $$\frac{2}{5}$$
3. 12$$\frac{4}{5}$$+6$$\frac{3}{5}$$ = (12 + 6) + ($$\frac{4}{5}$$ +$$\frac{3}{5}$$) = 18 + $$\frac{7}{5}$$ = 18 + 1$$\frac{2}{5}$$ = 19$$\frac{2}{5}$$

Ответ:

1. 11$$\frac{1}{5}$$
2. $$\frac{2}{5}$$
3. 19$$\frac{2}{5}$$