11) \(\frac{1}{4} + \frac{1}{12} + \frac{1}{12} + \frac{1}{12}\)

Решение:

\(\frac{1}{4} + \frac{1}{12} + \frac{1}{12} + \frac{1}{12} = \frac{1 \cdot 3}{4 \cdot 3} + \frac{1}{12} + \frac{1}{12} + \frac{1}{12} = \frac{3}{12} + \frac{1}{12} + \frac{1}{12} + \frac{1}{12} = \frac{3+1+1+1}{12} = \frac{6}{12} = \frac{1}{2}\)

Ответ: \(\frac{1}{2}\)