2. Найдите значение выражения: 6 a) 8-3 \frac{6}{7} = 1 5 6)2+312= 13 7 B) 5+112= 15 3 5 г) 70-30=

a) $$8 - 3\frac{6}{7} = 7\frac{7}{7} - 3\frac{6}{7} = (7-3) + (\frac{7}{7} - \frac{6}{7}) = 4\frac{1}{7}$$

б) $$2\frac{1}{8} + 3\frac{5}{12} = 2\frac{3}{24} + 3\frac{10}{24} = (2+3) + (\frac{3}{24} + \frac{10}{24}) = 5\frac{13}{24}$$

в) $$5\frac{13}{15} + 1\frac{7}{12} = 5\frac{52}{60} + 1\frac{35}{60} = (5+1) + (\frac{52}{60} + \frac{35}{60}) = 6 + \frac{87}{60} = 6 + 1\frac{27}{60} = 7\frac{27}{60} = 7\frac{9}{20}$$

г) $$7\frac{3}{8} - 3\frac{5}{6} = 7\frac{9}{24} - 3\frac{20}{24} = 6\frac{33}{24} - 3\frac{20}{24} = (6-3) + (\frac{33}{24} - \frac{20}{24}) = 3\frac{13}{24}$$

Ответ: a) $$4\frac{1}{7}$$; б) $$5\frac{13}{24}$$; в) $$7\frac{9}{20}$$; г) $$3\frac{13}{24}$$