У) \(\frac{\frac{7}{15}+\frac{14}{45}+\frac{2}{9}\cdot10-\frac{1}{3}-\frac{1}{11}\cdot(2\frac{2}{3}-1\frac{3}{4})}{(\frac{3}{7}:\frac{1}{4})\cdot\frac{3}{28}-1}\)

Решение:

Числитель:

1. \( \frac{2}{9} \cdot 10 = \frac{20}{9} \)
2. \( \frac{7}{15} + \frac{14}{45} + \frac{20}{9} = \frac{7\cdot3 + 14 + 20\cdot5}{45} = \frac{21 + 14 + 100}{45} = \frac{135}{45} = 3 \)
3. \( 2\frac{2}{3} = \frac{8}{3} \), \( 1\frac{3}{4} = \frac{7}{4} \)
4. \( \frac{8}{3} - \frac{7}{4} = \frac{32 - 21}{12} = \frac{11}{12} \)
5. \( \frac{1}{11} \cdot \frac{11}{12} = \frac{1}{12} \)
6. \( 3 - \frac{1}{3} - \frac{1}{12} = \frac{36 - 4 - 1}{12} = \frac{31}{12} \)

Знаменатель:

1. \( \frac{3}{7} : \frac{1}{4} = \frac{3}{7} \cdot 4 = \frac{12}{7} \)
2. \( \frac{12}{7} \cdot \frac{3}{28} = \frac{12\cdot3}{7\cdot28} = \frac{36}{196} = \frac{9}{49} \)
3. \( \frac{9}{49} - 1 = \frac{9 - 49}{49} = -\frac{40}{49} \)

Делим числитель на знаменатель:

1. \( \frac{31}{12} : (-\frac{40}{49}) = \frac{31}{12} \cdot (-\frac{49}{40}) = -\frac{31\cdot49}{12\cdot40} = -\frac{1519}{480} \)

Ответ: -\(\frac{1519}{480}\)