12 25 30) 100 4

$$\frac{12}{100} \cdot \frac{25}{4} = \frac{12 \cdot 25}{100 \cdot 4} = \frac{300}{400}$$

Сократим дробь на 100:

$$\frac{300:100}{400:100} = \frac{3}{4}$$

Ответ: $$\frac{3}{4}$$