Bonjour,
[tex] \frac{8}{2} + \frac{6}{4} = \frac{16}{4} + \frac{6}{4} = \frac{22}{4} = \frac{11}{2} [/tex]
[tex] \frac{-4}{5} - \frac{3}{10}= \frac{-8}{10}- \frac{3}{10}= \frac{-11}{10} [/tex]
[tex] \frac{7}{3} * \frac{5}{7} = \frac{35}{21} = \frac{5}{3} [/tex]
[tex] \frac{10}{12} * \frac{6}{5} * \frac{4}{2} = \frac{60}{60} * \frac{4}{2} =1* \frac{4}{2} =2[/tex]
[tex] \frac{6/5}{8/9} = \frac{6}{5} * \frac{9}{8}= \frac{54}{40} = \frac{27}{20} [/tex]
[tex] \frac{7/2}{-1/2} = \frac{7}{2} *-2= \frac{-14}{2}=-7 [/tex]
J'espère t'avoir aidé.