378. Найдите значение выражения: a) $$\frac{1}{4}-\left(1-\frac{11}{12}\right)$$; б) $$2-\left(\frac{13}{33}-\frac{5}{22}\right)$$; в) $$6\frac{3}{16}-\left(2\frac{3}{8}+3\frac{5}{12}\right)$$; г) $$8\frac{1}{12}-\frac{3}{15}-1\frac{7}{30}$$; д) $$\left(13-8\frac{5}{12}\right)+\left(17\frac{1}{2}-16\frac{5}{8}\right)$$; е) $$\left(63\frac{2}{3}+3\frac{1}{8}\right)-\left(13-10\frac{5}{9}\right)$$.

a) $$\frac{1}{4}-\left(1-\frac{11}{12}\right) = \frac{1}{4}-\left(\frac{12}{12}-\frac{11}{12}\right) = \frac{1}{4}-\frac{1}{12} = \frac{3}{12}-\frac{1}{12} = \frac{2}{12} = \frac{1}{6}$$; б) $$2-\left(\frac{13}{33}-\frac{5}{22}\right) = 2-\left(\frac{26}{66}-\frac{15}{66}\right) = 2-\frac{11}{66} = 2-\frac{1}{6} = \frac{12}{6}-\frac{1}{6} = \frac{11}{6} = 1\frac{5}{6}$$; в) $$6\frac{3}{16}-\left(2\frac{3}{8}+3\frac{5}{12}\right) = 6\frac{3}{16}-\left(2\frac{9}{24}+3\frac{10}{24}\right) = 6\frac{3}{16}-5\frac{19}{24} = 6\frac{9}{48}-5\frac{38}{48} = 5\frac{57}{48}-5\frac{38}{48} = \frac{19}{48}$$; г) $$8\frac{1}{12}-\frac{3}{15}-1\frac{7}{30} = 8\frac{1}{12}-\frac{1}{5}-1\frac{7}{30} = 8\frac{5}{60}-\frac{12}{60}-1\frac{14}{60} = 8\frac{5}{60}-\frac{12}{60}-1\frac{14}{60} = 7\frac{65}{60}-\frac{12}{60}-1\frac{14}{60} = 7\frac{53}{60}-1\frac{14}{60} = 6\frac{39}{60} = 6\frac{13}{20}$$; д) $$\left(13-8\frac{5}{12}\right)+\left(17\frac{1}{2}-16\frac{5}{8}\right) = \left(12\frac{12}{12}-8\frac{5}{12}\right)+\left(17\frac{4}{8}-16\frac{5}{8}\right) = 4\frac{7}{12}+\frac{7}{8} = 4\frac{14}{24}+\frac{21}{24} = 4\frac{35}{24} = 5\frac{11}{24}$$; е) $$\left(63\frac{2}{3}+3\frac{1}{8}\right)-\left(13-10\frac{5}{9}\right) = \left(63\frac{16}{24}+3\frac{3}{24}\right)-\left(12\frac{9}{9}-10\frac{5}{9}\right) = 66\frac{19}{24}-2\frac{4}{9} = 66\frac{57}{72}-2\frac{32}{72} = 64\frac{25}{72}$$. Ответ: a) $$\frac{1}{6}$$; б) $$1\frac{5}{6}$$; в) $$\frac{19}{48}$$; г) $$6\frac{13}{20}$$; д) $$5\frac{11}{24}$$; е) $$64\frac{25}{72}$$