[tex]\displaystyle\\
_\texttt{\bf Impartirea a doua fractii se face} \\ _\texttt{\bf inmultind prima fractie cu factia a doua rasturnata.}\\\\
\frac{3}{7} : \frac{5}{4}= \frac{3}{7} \times \frac{4}{5}=\frac{3\times4}{7\times5}= \boxed{\frac{12}{35}}\\\\
\frac{10}{9}: \frac{15}{21} = \frac{10}{9}\times \frac{21}{15} = \frac{10\times 21}{9\times 15}= \frac{2\times 7}{3\times 3}= \boxed{\frac{14}{9}}
[/tex]