$$5m \cdot \frac{2}{11}c \cdot \frac{6}{2} \cdot \frac{5}{14}k = \frac{5 \cdot 2 \cdot 6 \cdot 5}{11 \cdot 2 \cdot 14}mck = \frac{300}{308}mck = \frac{75}{77}mck$$
Ответ: $$\frac{75}{77}mck$$