номер 828 Помогите пожалуйста за 5 минут

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