1. a) 6$$\frac{2}{7}$$+1 б) 5 - $$\frac{1}{3}$$ в) 7$$\frac{5}{8}$$ + 3$$\frac{1}{8}$$ г) 5$$\frac{3}{10}$$ - 2$$\frac{1}{5}$$

Решение:

a) $$6\frac{2}{7} + 1 = 7\frac{2}{7}$$

б) $$5 - \frac{1}{3} = \frac{5}{1} - \frac{1}{3} = \frac{5 \cdot 3}{1 \cdot 3} - \frac{1}{3} = \frac{15}{3} - \frac{1}{3} = \frac{15-1}{3} = \frac{14}{3} = 4\frac{2}{3}$$

в) $$7\frac{5}{8} + 3\frac{1}{8} = (7+3) + (\frac{5}{8} + \frac{1}{8}) = 10 + \frac{5+1}{8} = 10 + \frac{6}{8} = 10 + \frac{3}{4} = 10\frac{3}{4}$$

г) $$5\frac{3}{10} - 2\frac{1}{5} = 5\frac{3}{10} - 2\frac{1 \cdot 2}{5 \cdot 2} = 5\frac{3}{10} - 2\frac{2}{10} = (5-2) + (\frac{3}{10} - \frac{2}{10}) = 3 + \frac{3-2}{10} = 3 + \frac{1}{10} = 3\frac{1}{10}$$

Ответ: a) $$7\frac{2}{7}$$, б) $$4\frac{2}{3}$$, в) $$10\frac{3}{4}$$, г) $$3\frac{1}{10}$$