1. Вычислите: a) $$4\frac{3}{10} + 1\frac{5}{12}$$; б) $$5\frac{1}{6} - 3\frac{3}{4}$$; в) $$3\frac{5}{7} \cdot 1\frac{1}{13}$$; г) $$7\frac{11}{12} : 3\frac{1}{6}$$.

Решение: a) $$4\frac{3}{10} + 1\frac{5}{12} = 4\frac{18}{60} + 1\frac{25}{60} = 5\frac{43}{60}$$. б) $$5\frac{1}{6} - 3\frac{3}{4} = 5\frac{2}{12} - 3\frac{9}{12} = 4\frac{14}{12} - 3\frac{9}{12} = 1\frac{5}{12}$$. в) $$3\frac{5}{7} \cdot 1\frac{1}{13} = \frac{26}{7} \cdot \frac{14}{13} = \frac{26 \cdot 14}{7 \cdot 13} = \frac{2 \cdot 2}{1 \cdot 1} = 4$$. г) $$7\frac{11}{12} : 3\frac{1}{6} = \frac{95}{12} : \frac{19}{6} = \frac{95}{12} \cdot \frac{6}{19} = \frac{95 \cdot 6}{12 \cdot 19} = \frac{5 \cdot 1}{2 \cdot 1} = \frac{5}{2} = 2\frac{1}{2}$$. Ответ: a) $$5\frac{43}{60}$$; б) $$1\frac{5}{12}$$; в) 4; г) $$2\frac{1}{2}$$.