\( 5 \frac{5}{12} + 1 \frac{1}{12} = 5 + 1 + \frac{5}{12} + \frac{1}{12} = 6 + \frac{6}{12} = 6 + \frac{1}{2} = 6,5 \) м.
\( P = 2 \cdot (5 \frac{5}{12} + 6,5) = 2 \cdot (5 \frac{5}{12} + 6 \frac{6}{12}) = 2 \cdot (11 \frac{11}{12}) = 22 \frac{22}{12} = 23 \frac{10}{12} = 23 \frac{5}{6} \) м.
Ответ: Периметр прямоугольника равен 23 5/6 м.