1. $$2\frac{1}{3} : \left(\frac{5}{8} - \frac{8}{3}\right) - 2 \cdot 1\frac{3}{7}$$

INSIGHT

Решение:

1. \(\frac{5}{8} - \frac{8}{3} = \frac{5 \cdot 3 - 8 \cdot 8}{8 \cdot 3} = \frac{15 - 64}{24} = -\frac{49}{24}\)
2. \(2\frac{1}{3} = \frac{7}{3}\)
3. \(1\frac{3}{7} = \frac{10}{7}\)
4. \(-\frac{49}{24} \cdot \frac{7}{3} = -\frac{49 \cdot 7}{24 \cdot 3} = -\frac{343}{72}\)
5. \(2 \cdot \frac{10}{7} = \frac{20}{7}\)
6. \(\frac{7}{3} : \left(-\frac{49}{24}\right) = \frac{7}{3} \cdot \left(-\frac{24}{49}\right) = -\frac{7 \cdot 24}{3 \cdot 49} = -\frac{1 \cdot 8}{1 \cdot 7} = -\frac{8}{7}\)
7. \(-\frac{8}{7} - \frac{20}{7} = -\frac{28}{7} = -4\)

Ответ: -4