53. Найдите значение выражения: а) \(\frac49+\frac79-\frac19\); б) \(\frac67-\left(\frac57-\frac17\right)\); в) \(5\frac6{39}+4\frac7{78}\); г) \(7\frac{13}{15}-8\frac{11}{30}\); д) \(\frac78\cdot\frac4{35}\cdot\frac{10}{9}\); е) \(\left(\frac12:\frac34-\frac49\right)\cdot\frac53\).

1. \(\frac49+\frac79-\frac19=\frac{4+7-1}{9}=\frac{10}{9}=1\frac19\).

2. \(\frac67-\left(\frac57-\frac17\right)=\frac67-\frac47=\frac27\).

3. \(5\frac6{39}+4\frac7{78}=9+\frac{12}{78}+\frac7{78}=9\frac{19}{78}\).

4. \(7\frac{13}{15}-8\frac{11}{30}=7\frac{26}{30}-8\frac{11}{30}=-1\frac{15}{30}=-1\frac12\).

5. \(\frac78\cdot\frac4{35}\cdot\frac{10}{9}=\frac19\).

6. \(\left(\frac12:\frac34-\frac49\right)\cdot\frac53=\left(\frac23-\frac49\right)\cdot\frac53=\frac29\cdot\frac53=\frac{10}{27}\).

Ответ: а) \(1\frac19\); б) \(\frac27\); в) \(9\frac{19}{78}\); г) \(-1\frac12\); д) \(\frac19\); е) \(\frac{10}{27}\).