4.Решите уравнение a) \(\frac{5}{6}\) * x = 25 5. Выполните действия a) \(3\frac{3}{4} * 2\frac{2}{9}\) б) \(\frac{20}{63} : x = \frac{4}{7}\) б) \(3\frac{5}{6} : 8\frac{1}{3}\)

4. Решите уравнение.
a) \(\frac{5}{6} \cdot x = 25\) \[x = 25 : \frac{5}{6}\] \[x = 25 \cdot \frac{6}{5}\] \[x = \frac{25 \cdot 6}{5}\] \[x = \frac{5 \cdot 6}{1}\] \[x = 30\]
б) \(\frac{20}{63} : x = \frac{4}{7}\) \[x = \frac{20}{63} : \frac{4}{7}\] \[x = \frac{20}{63} \cdot \frac{7}{4}\] \[x = \frac{20 \cdot 7}{63 \cdot 4}\] \[x = \frac{5 \cdot 1}{9 \cdot 1}\] \[x = \frac{5}{9}\] 5. Выполните действия.
a) \(3\frac{3}{4} \cdot 2\frac{2}{9}\) \[3\frac{3}{4} = \frac{3 \cdot 4 + 3}{4} = \frac{12 + 3}{4} = \frac{15}{4}\] \[2\frac{2}{9} = \frac{2 \cdot 9 + 2}{9} = \frac{18 + 2}{9} = \frac{20}{9}\] \[\frac{15}{4} \cdot \frac{20}{9} = \frac{15 \cdot 20}{4 \cdot 9} = \frac{5 \cdot 5}{1 \cdot 3} = \frac{25}{3} = 8\frac{1}{3}\]
б) \(3\frac{5}{6} : 8\frac{1}{3}\) \[3\frac{5}{6} = \frac{3 \cdot 6 + 5}{6} = \frac{18 + 5}{6} = \frac{23}{6}\] \[8\frac{1}{3} = \frac{8 \cdot 3 + 1}{3} = \frac{24 + 1}{3} = \frac{25}{3}\] \[\frac{23}{6} : \frac{25}{3} = \frac{23}{6} \cdot \frac{3}{25} = \frac{23 \cdot 3}{6 \cdot 25} = \frac{23 \cdot 1}{2 \cdot 25} = \frac{23}{50}\]