Уважаемые,помогите с 997 номером. Мучаюсь с этими дробями,муторно ей богу,помогите...

Решите задачу:

$\displaystyle \tt 1). \ \ 9\frac{2}{3}+1\frac{1}{4}=10+\bigg(\frac{8}{12}+\frac{3}{12}\bigg)=10\frac{11}{12};\\\\2). \ \ 13\frac{1}{5}+4\frac{2}{7}=17+\bigg(\frac{7}{35}+\frac{10}{35}\bigg)=17\frac{17}{35};\\\\3). \ \ 2\frac{3}{10}+6\frac{1}{9}=8+\bigg(\frac{27}{90}+\frac{10}{90}\bigg)=8\frac{37}{90};\\\\4). \ \ 4\frac{2}{3}+7\frac{4}{5}=11+\bigg(\frac{10}{15}+\frac{12}{15}\bigg)=11\frac{22}{15}=12\frac{7}{15};$

$\displaystyle \tt 5). \ \ 7\frac{3}{20}+8\frac{4}{5}=15+\bigg(\frac{3}{20}+\frac{16}{20}\bigg)=15\frac{19}{20};\\\\6). \ \ 2\frac{7}{48}+11\frac{77}{96}=13+\bigg(\frac{14}{96}+\frac{77}{96}\bigg)=13\frac{91}{96};$