554. Выполните действия: a) (1$$\frac{2}{9}$$ + 1$$\frac{1}{6}$$) $$\cdot$$ (2 - 1$$\frac{25}{42}$$); б) (4 + 2$$\frac{7}{15}$$) $$\cdot$$ (10 - 8$$\frac{16}{23}$$); в) (4 + 5$$\frac{1}{6}$$) $$\cdot$$ (3$$\frac{2}{3}$$ - $$\frac{13}{33}$$); г) 6$$\frac{5}{12}$$ $$\cdot$$ $$\frac{4}{11}$$ - 11$$\frac{1}{4}$$ $$\cdot$$ $$\frac{1}{9}$$.

Решим по действиям: а) 1. 1$$\frac{2}{9}$$ + 1$$\frac{1}{6}$$ = $$\frac{11}{9}$$ + $$\frac{7}{6}$$ = $$\frac{22}{18}$$ + $$\frac{21}{18}$$ = $$\frac{43}{18}$$; 2. 1$$\frac{25}{42}$$ = $$\frac{67}{42}$$; 3. 2 - 1$$\frac{25}{42}$$ = $$\frac{2}{1}$$ - $$\frac{67}{42}$$ = $$\frac{84}{42}$$ - $$\frac{67}{42}$$ = $$\frac{17}{42}$$; 4. $$\frac{43}{18}$$ $$\cdot$$ $$\frac{17}{42}$$ = $$\frac{731}{756}$$. б) 1. 2$$\frac{7}{15}$$ = $$\frac{37}{15}$$; 2. 4 + 2$$\frac{7}{15}$$ = $$\frac{4}{1}$$ + $$\frac{37}{15}$$ = $$\frac{60}{15}$$ + $$\frac{37}{15}$$ = $$\frac{97}{15}$$; 3. 8$$\frac{16}{23}$$ = $$\frac{200}{23}$$; 4. 10 - 8$$\frac{16}{23}$$ = $$\frac{10}{1}$$ - $$\frac{200}{23}$$ = $$\frac{230}{23}$$ - $$\frac{200}{23}$$ = $$\frac{30}{23}$$; 5. $$\frac{97}{15}$$ $$\cdot$$ $$\frac{30}{23}$$ = $$\frac{97}{1}$$ $$\cdot$$ $$\frac{2}{23}$$ = $$\frac{194}{23}$$ = 8$$\frac{10}{23}$$. в) 1. 5$$\frac{1}{6}$$ = $$\frac{31}{6}$$; 2. 4 + 5$$\frac{1}{6}$$ = $$\frac{4}{1}$$ + $$\frac{31}{6}$$ = $$\frac{24}{6}$$ + $$\frac{31}{6}$$ = $$\frac{55}{6}$$; 3. 3$$\frac{2}{3}$$ = $$\frac{11}{3}$$; 4. $$\frac{11}{3}$$ - $$\frac{13}{33}$$ = $$\frac{121}{33}$$ - $$\frac{13}{33}$$ = $$\frac{108}{33}$$ = $$\frac{36}{11}$$; 5. $$\frac{55}{6}$$ $$\cdot$$ $$\frac{36}{11}$$ = $$\frac{5}{1}$$ $$\cdot$$ $$\frac{6}{1}$$ = 30. г) 1. 6$$\frac{5}{12}$$ = $$\frac{77}{12}$$; 2. 11$$\frac{1}{4}$$ = $$\frac{45}{4}$$; 3. $$\frac{45}{4}$$ $$\cdot$$ $$\frac{1}{9}$$ = $$\frac{5}{4}$$ $$\cdot$$ $$\frac{1}{1}$$ = $$\frac{5}{4}$$; 4. $$\frac{77}{12}$$ $$\cdot$$ $$\frac{4}{11}$$ = $$\frac{7}{3}$$ $$\cdot$$ $$\frac{1}{1}$$ = $$\frac{7}{3}$$; 5. $$\frac{7}{3}$$ - $$\frac{5}{4}$$ = $$\frac{28}{12}$$ - $$\frac{15}{12}$$ = $$\frac{13}{12}$$ = 1$$\frac{1}{12}$$.