6 целых - 13 целых 1/4 : (-0.8- 9 целых 4/5) помогите пожужда

Решите задачу:

$\displaystyle\tt 6-13\frac{1}{4}:(-0.8 -9 \frac{4}{5}\Big)=6-\frac{53}{4}:\Big(-\frac{8}{10} -\frac{49}{5}\Big)=\\\\\\=\frac{24-53}{4}:\Big(\frac{-8-98}{10}\Big)=-\frac{29}{4}:\Big(-\frac{106}{10} \Big)=\\\\\\=-\frac{29}{4} \cdot \Big(-\frac{10}{106} \Big)=\frac{29\cdot5}{2\cdot106}=\frac{145}{212}$