Вычисление значения числового выражения

1)

$$14\frac{7}{15}-3\frac{3}{23}\cdot \frac{23}{27}-1\frac{1}{5}\cdot \frac{1}{6} = \frac{217}{15} - \frac{72}{23} \cdot \frac{23}{27} - \frac{6}{5} \cdot \frac{1}{6} = $$ $$= \frac{217}{15} - \frac{72}{27} - \frac{1}{5} = \frac{217}{15} - \frac{8}{3} - \frac{1}{5} = \frac{217}{15} - \frac{40}{15} - \frac{3}{15} = \frac{217-40-3}{15} = \frac{174}{15} = \frac{58}{5} = 11\frac{3}{5}$$

Ответ: $$11\frac{3}{5}$$

2)

$$\left(5\frac{8}{9}:1\frac{17}{36}+1\frac{1}{4}\right)\cdot \frac{5}{21} = \left(\frac{53}{9}:\frac{53}{36}+\frac{5}{4}\right)\cdot \frac{5}{21} = \left(\frac{53}{9}\cdot \frac{36}{53}+\frac{5}{4}\right)\cdot \frac{5}{21} = $$ $$=\left(4+\frac{5}{4}\right)\cdot \frac{5}{21} = \left(\frac{16}{4}+\frac{5}{4}\right)\cdot \frac{5}{21} = \frac{21}{4}\cdot \frac{5}{21} = \frac{5}{4} = 1\frac{1}{4}$$

Ответ: $$1\frac{1}{4}$$

3)

$$(-3,25-2,75):(-0,6)+0,8\cdot (-7) = (-6):(-0,6)+0,8\cdot (-7) = $$ $$= 10 - 5,6 = 4,4$$

Ответ: $$4,4$$

4)

$$\left(-1\frac{3}{8}-2\frac{5}{12}\right):5\frac{5}{12} = \left(-\frac{11}{8}-\frac{29}{12}\right):\frac{65}{12} = \left(-\frac{33}{24}-\frac{58}{24}\right):\frac{65}{12} = $$ $$=-\frac{91}{24}:\frac{65}{12} = -\frac{91}{24}\cdot \frac{12}{65} = -\frac{91}{2}\cdot \frac{1}{65} = -\frac{7}{2}\cdot \frac{1}{5} = -\frac{7}{10} = -0,7$$

Ответ: $$-0,7$$