Bonjour,
[tex]A=\frac{7}{9}+\frac{11}{15} \\A=\frac{7\times5}{9\times5} +\frac{11\times3}{15\times3} \\A=\frac{35}{33} +\frac{33}{45} \\A=\frac{35+33}{45}\\A =\frac{68}{45}[/tex]
[tex]B=\frac{13}{16} \times8\\B=\frac{13}{2}[/tex]
[tex]C=\frac{5}{6} \times\frac{4}{10}+\frac{3}{10}\\C=\frac{1}{6}\times\frac{4}{2} +\frac{3}{10}\\C=\frac{1}{3}\times\frac{2}{2}+\frac{3}{10}\\C=\frac{1}{3}+\frac{3}{10}\\C=\frac{10+9}{30}\\C=\frac{19}{30}[/tex]
