Вычисления и преобразования

$$\frac{7\sqrt{3}-5}{\sqrt{3}} + \frac{5\sqrt{3}}{3} + 3 \cdot 3 - 4 = 7 - \frac{5}{\sqrt{3}} + \frac{5}{\sqrt{3}} + 9 - 4 = 7 + 9 - 4 = 12$$

$$\left(\frac{18}{7} - \frac{5}{2}\right) \cdot 70 = \left(\frac{36}{14} - \frac{35}{14}\right) \cdot 70 = \frac{1}{14} \cdot 70 = 5$$

$$\frac{(432-568)(432+568)}{1000} = \frac{(-136)(1000)}{1000} = -136$$

$$\frac{40}{9} \cdot \frac{9}{4} = 10$$

$$\frac{1,23 \cdot 45,7}{12,3 \cdot 0,457} = \frac{1,23 \cdot 45,7}{1,23 \cdot 10 \cdot \frac{45,7}{100}} = \frac{1}{10 \cdot \frac{1}{100}} = 10$$