15km²p-45km 60 kmp²

Сократим дробь (15km²p-45km)/(60 kmp²):

$$ \frac{15km^2p-45km}{60kmp^2} = \frac{15km(kp-3)}{60kmp^2} = \frac{15}{60} \cdot \frac{k}{k} \cdot \frac{m}{m} \cdot \frac{kp-3}{p^2} = \frac{1}{4} \cdot 1 \cdot 1 \cdot \frac{kp-3}{p^2} = \frac{kp-3}{4p^2}$$

Ответ: (kp-3)/(4p²)