Ответ:

  1. \(\frac49\cdot\frac3{16}=\frac1{12}\).
  2. \(\frac59\cdot4\frac12=\frac59\cdot\frac92=\frac52=2\frac12\).
  3. \(5\cdot\frac3{25}=\frac35\).
  4. \(1\frac19\cdot18=\frac{10}{9}\cdot18=20\).
  5. \(1\frac18\cdot2\frac23=\frac98\cdot\frac83=3\).
  6. \(\frac58:\frac{15}{16}=\frac58\cdot\frac{16}{15}=\frac23\).
  7. \(2\frac25:6=\frac{12}{5}:6=\frac25\).
  8. \(8:\frac49=8\cdot\frac94=18\).
  9. \(3\frac12:1\frac34=\frac72:\frac74=2\).

Ответ: а) \(\frac1{12}\); б) \(2\frac12\); в) \(\frac35\); г) \(20\); д) \(3\); е) \(\frac23\); ж) \(\frac25\); з) \(18\); и) \(2\).