\[\frac{1\frac{1}{7}}{14} = \frac{\frac{8}{7}}{14} = \frac{8}{7} \cdot \frac{1}{14} = \frac{8}{98} = \frac{4}{49}\]
\[\frac{3\frac{3}{5}}{25} = \frac{\frac{18}{5}}{25} = \frac{18}{5} \cdot \frac{1}{25} = \frac{18}{125}\]
\[\frac{3}{14} \cdot 7 - 1\frac{3}{4} = \frac{3}{14} \cdot \frac{7}{1} - \frac{7}{4} = \frac{3 \cdot 7}{14} - \frac{7}{4} = \frac{21}{14} - \frac{7}{4} = \frac{3}{2} - \frac{7}{4} = \frac{6}{4} - \frac{7}{4} = -\frac{1}{4}\]
Ответ: а) 4/49; б) 18/125; в) -1/4