339. Найдите произведение: 1) 0,4 · 5/9; 2) 8/27 · 0,75; 3) 1,5 · 1/6; 4) 2 1/7 · 2,8.

1. \(0.4\cdot\frac{5}{9}=\frac{2}{5}\cdot\frac{5}{9}=\frac{2}{9}\).
2. \(\frac{8}{27}\cdot0.75=\frac{8}{27}\cdot\frac{3}{4}=\frac{2}{9}\).
3. \(1.5\cdot\frac{1}{6}=\frac{3}{2}\cdot\frac{1}{6}=\frac{1}{4}\).
4. \(2\frac{1}{7}\cdot2.8=\frac{15}{7}\cdot\frac{14}{5}=6\).

Ответ: 1) \(\frac{2}{9}\); 2) \(\frac{2}{9}\); 3) \(\frac{1}{4}\); 4) \(6\).