2.53. Найдите значение выражения: а) \(\frac49+\frac79-\frac19\); б) \(\frac97\cdot(\frac57-\frac17)\); в) \(5\frac6{39}+4\frac7{78}\); г) \(7\frac{13}{15}-3\frac{11}{30}\); д) \(\frac78\cdot\frac4{35}\cdot\frac{10}{9}\); е) \((\frac12:\frac34-\frac49)\cdot\frac53\).

1. \(\frac49+\frac79-\frac19=\frac{10}{9}=1\frac19\).
2. \(\frac97\cdot(\frac57-\frac17)=\frac97\cdot\frac47=\frac{36}{49}\).
3. \(5\frac6{39}+4\frac7{78}=9+\frac{12}{78}+\frac7{78}=9\frac{19}{78}\).
4. \(7\frac{13}{15}-3\frac{11}{30}=4+\frac{26}{30}-\frac{11}{30}=4\frac12\).
5. \(\frac78\cdot\frac4{35}\cdot\frac{10}{9}=\frac19\).
6. \((\frac12:\frac34-\frac49)\cdot\frac53=(\frac23-\frac49)\cdot\frac53=\frac29\cdot\frac53=\frac{10}{27}\).

Ответ: а) \(1\frac19\); б) \(\frac{36}{49}\); в) \(9\frac{19}{78}\); г) \(4\frac12\); д) \(\frac19\); е) \(\frac{10}{27}\).