17. Выполните действия: а) \(\frac{5}{6}+\frac{1}{4}\); б) \(\frac{3}{10}-\frac{4}{15}\); в) \(5-3\frac{2}{7}\); г) \(\frac{5}{12}:\frac{4}{9}\); д) \(\frac{5}{8}\cdot(-6)\); е) \(-\frac{5}{9}\cdot3\); ж) \(\frac{6}{5}:1\frac{3}{7}\); з) \(6\frac{2}{3}\cdot10\).

1. а) \(\frac56+\frac14=\frac{10}{12}+\frac3{12}=\frac{13}{12}=1\frac1{12}\);
2. б) \(\frac3{10}-\frac4{15}=\frac9{30}-\frac8{30}=\frac1{30}\);
3. в) \(5-3\frac27=\frac{35}{7}-\frac{23}{7}=\frac{12}{7}=1\frac57\);
4. г) \(\frac5{12}:\frac49=\frac5{12}\cdot\frac94=\frac{15}{16}\);
5. д) \(\frac58\cdot(-6)=-\frac{15}{4}=-3\frac34\);
6. е) \(-\frac59\cdot3=-\frac53\);
7. ж) \(\frac65:1\frac37=\frac65:\frac{10}{7}=\frac65\cdot\frac7{10}=\frac7{12}\);
8. з) \(6\frac23\cdot10=\frac{20}{3}\cdot10=\frac{200}{3}=66\frac23\).

Ответ: \(1\frac1{12};\frac1{30};1\frac57;\frac{15}{16};-3\frac34;-\frac53;\frac7{12};66\frac23\).