2. Выполните действия a) \(1\frac{5}{19} \cdot (6-3\frac{5}{8})\) б) \((6,3:1,4-2,05) \cdot 1,8\)

a) \(1\frac{5}{19} \cdot (6-3\frac{5}{8}) = \frac{24}{19} \cdot (\frac{6}{1} - \frac{29}{8}) = \frac{24}{19} \cdot (\frac{6 \cdot 8}{1 \cdot 8} - \frac{29}{8}) = \frac{24}{19} \cdot (\frac{48}{8} - \frac{29}{8}) = \frac{24}{19} \cdot \frac{19}{8} = \frac{24 \cdot 19}{19 \cdot 8} = \frac{3 \cdot 8 \cdot 19}{19 \cdot 8} = 3\)

б) \((6,3:1,4-2,05) \cdot 1,8 = (6,3 : 1,4 - 2,05) \cdot 1,8 = (4,5 - 2,05) \cdot 1,8 = 2,45 \cdot 1,8 = 4,41\)

Ответ: a) \(3\); б) \(4,41\)