a) Сократим дробь $$\frac{75b^5c^3}{50b^4c^4}$$
$$\frac{75b^5c^3}{50b^4c^4} = \frac{3 \times 25 \times b^4 \times b \times c^3}{2 \times 25 \times b^4 \times c^3 \times c} = \frac{3b}{2c}$$
Ответ: $$\frac{3b}{2c}$$