3 1,1⋅1\frac{1}{6}:0,05 7 a) 1 : 0,25 ⋅ 2\frac{2}{5} 7

a) Выполним действия:

$$ \frac{\frac{3}{7} \cdot 1,1 \cdot 1 \frac{1}{6}}{ \frac{1}{7}: 0,25 \cdot 2 \frac{2}{5}} = \frac{\frac{3}{7} \cdot \frac{11}{10} \cdot \frac{7}{6}}{ \frac{1}{7}: \frac{1}{4} \cdot \frac{12}{5}} = \frac{\frac{3 \cdot 11 \cdot 7}{7 \cdot 10 \cdot 6}}{ \frac{1 \cdot 4 \cdot 12}{7 \cdot 1 \cdot 5}} = \frac{\frac{231}{420}}{ \frac{48}{35}} = \frac{231}{420} : \frac{48}{35} = \frac{231 \cdot 35}{420 \cdot 48} = \frac{8085}{20160} = \frac{7 \cdot 1155}{7 \cdot 2880} = \frac{1155}{2880} = \frac{5 \cdot 231}{5 \cdot 576} = \frac{231}{576} = \frac{3 \cdot 77}{3 \cdot 192} = \frac{77}{192} $$

Ответ: $$\frac{77}{192}$$