Выполните действия: 3 1/12+2 1/6-1/8 а) 1,4+0,6*4,5 10 10/11:12 б) *6 1/2; 2 21/22 8:2 2/5 2 1/7:5/7 в) : 5 1/4:7 4:8/9

a)

$$\frac{3 \frac{1}{12} + 2 \frac{1}{6} - \frac{1}{8}}{1,4 + 0,6 \cdot 4,5} = \frac{3 + \frac{1}{12} + 2 + \frac{1}{6} - \frac{1}{8}}{1,4 + 2,7} = \frac{5 + \frac{2}{24} + \frac{4}{24} - \frac{3}{24}}{4,1} = \frac{5 + \frac{3}{24}}{4,1} = \frac{5 \frac{1}{8}}{4,1} = \frac{41}{8} : \frac{41}{10} = \frac{41}{8} \cdot \frac{10}{41} = \frac{10}{8} = \frac{5}{4} = 1 \frac{1}{4}$$.

б)

$$\frac{10 \frac{10}{11} : 12}{2 \frac{21}{22}} \cdot 6 \frac{1}{2} = \frac{\frac{120}{11}:12}{\frac{65}{22}} \cdot \frac{13}{2} = \frac{120}{11} \cdot \frac{1}{12} : \frac{65}{22} \cdot \frac{13}{2} = \frac{10}{11} \cdot \frac{22}{65} \cdot \frac{13}{2} = \frac{20}{65} \cdot \frac{13}{2} = \frac{4}{13} \cdot \frac{13}{2} = 2$$.

в)

$$\frac{8 : 2 \frac{2}{5}}{5 \frac{1}{4}:7} : \frac{2 \frac{1}{7} : \frac{5}{7}}{4 : \frac{8}{9}} = \frac{8 : \frac{12}{5}}{\frac{21}{4} : 7} : \frac{\frac{15}{7} : \frac{5}{7}}{4 : \frac{8}{9}} = \frac{8 \cdot \frac{5}{12}}{\frac{21}{4} \cdot \frac{1}{7}} : \frac{\frac{15}{7} \cdot \frac{7}{5}}{4 \cdot \frac{9}{8}} = \frac{\frac{10}{3}}{\frac{3}{4}} : \frac{3}{\frac{9}{2}} = \frac{10}{3} \cdot \frac{4}{3} : \frac{3 \cdot 2}{9} = \frac{40}{9} : \frac{2}{3} = \frac{40}{9} \cdot \frac{3}{2} = \frac{20}{3} = 6 \frac{2}{3}$$.

Ответ: а) $$1 \frac{1}{4}$$, б) 2, в) $$6 \frac{2}{3}$$.