$2\frac{1}{3} : 5\frac{5}{6} = \frac{7}{3} : \frac{35}{6} = \frac{7}{3} * \frac{6}{35} = \frac{1}{1} * \frac{2}{5} = \frac{2}{5}$
$\frac{2}{5} * 15 = 2 * 3 = 6$
$6 - 2\frac{13}{17} = 5\frac{17}{17} - 2\frac{13}{17} = 3\frac{4}{17}$
$3\frac{4}{17} * 1\frac{6}{11} = \frac{55}{17} * \frac{17}{11} = \frac{5}{1} * \frac{1}{1} = 5$
Ответ: → $\frac{2}{3}$ → 6 → $3\frac{4}{17}$ → 5.