40. Сократите: 1) \(\frac{6\cdot14}{7\cdot30}\); 2) \(\frac{22\cdot10}{15\cdot33}\); 3) \(\frac{9\cdot2\cdot3}{8\cdot18\cdot21}\); 4) \(\frac{8\cdot7+8\cdot3}{16\cdot25-16\cdot5}\).

1. \(\frac{6\cdot14}{7\cdot30}=\frac{84}{210}=\frac{2}{5}\).
2. \(\frac{22\cdot10}{15\cdot33}=\frac{220}{495}=\frac{4}{9}\).
3. \(\frac{9\cdot2\cdot3}{8\cdot18\cdot21}=\frac{54}{3024}=\frac{1}{56}\).
4. \(\frac{8\cdot7+8\cdot3}{16\cdot25-16\cdot5}=\frac{56+24}{400-80}=\frac{80}{320}=\frac{1}{4}\).

Ответ: 1) \(\frac{2}{5}\); 2) \(\frac{4}{9}\); 3) \(\frac{1}{56}\); 4) \(\frac{1}{4}\).