1. Вычисли: 5 14 1) 1) 725 5 2) 40.8 3)( 4-57 7 2 4) 0.0; ; ; 5) 8.16 9 6) 14: Выполни действия: 5 2 31 +5:15 - 2 2 7) 7): : 14; 22 : 8) デデ 9.5. 9

1)

\[\frac{5}{7} \cdot \frac{14}{25} = \frac{5 \cdot 14}{7 \cdot 25} = \frac{5 \cdot 2 \cdot 7}{7 \cdot 5 \cdot 5} = \frac{2}{5}\]

2)

\[40 \cdot \frac{5}{8} = \frac{40 \cdot 5}{8} = \frac{5 \cdot 8 \cdot 5}{8} = 25\]

3)

\[(\frac{4}{5})^2 = \frac{4^2}{5^2} = \frac{16}{25}\]

4)

\[\frac{7}{9} \cdot 0 = 0\]

5)

\[\frac{8}{9} : \frac{16}{27} = \frac{8}{9} \cdot \frac{27}{16} = \frac{8 \cdot 27}{9 \cdot 16} = \frac{8 \cdot 3 \cdot 9}{9 \cdot 2 \cdot 8} = \frac{3}{2} = 1 \frac{1}{2}\]

6)

\[14 : \frac{2}{7} = 14 \cdot \frac{7}{2} = \frac{14 \cdot 7}{2} = \frac{2 \cdot 7 \cdot 7}{2} = 49\]

7)

\[\frac{2}{7} : 14 = \frac{2}{7} \cdot \frac{1}{14} = \frac{2 \cdot 1}{7 \cdot 14} = \frac{2}{7 \cdot 2 \cdot 7} = \frac{1}{49}\]

8)

\[\frac{2}{7} : \frac{2}{7} = 1\]

9)

\[0 : \frac{2}{7} = 0 \cdot \frac{7}{2} = 0\]

10)

\[\frac{2}{7} : 0 = \text{не определено}\]

11)

\[1 : \frac{3}{11} = 1 \cdot \frac{11}{3} = \frac{11}{3} = 3 \frac{2}{3}\]

12)

\[\frac{3}{11} : 1 = \frac{3}{11}\]