Ответ:

  1. \(3\frac{2}{7}=\frac{3\cdot7+2}{7}=\frac{23}{7}\).
  2. \(13\frac{5}{12}=\frac{13\cdot12+5}{12}=\frac{161}{12}\).
  3. \(7\frac{4}{11}=\frac{7\cdot11+4}{11}=\frac{81}{11}\).
  4. \(23\frac{3}{5}=\frac{23\cdot5+3}{5}=\frac{118}{5}\).

Ответ: А. \(\frac{23}{7}\); Б. \(\frac{161}{12}\); В. \(\frac{81}{11}\); Г. \(\frac{118}{5}\).