Bonjour !
[tex]A=\frac{3}{7} +\frac{8}{7} \\A=\frac{3+8}{7} \\\boxed{A=\frac{11}{7}}[/tex]
[tex]B=\frac{5}{3} -8\\B=\frac{5}{3} -\frac{24}{3} \\B=\frac{5-24}{3}\\\boxed{B=-\frac{19}{3}}[/tex]
[tex]C=\frac{254}{10} \times\frac{5}{254} \\C=\frac{254\times 5}{10\times254} \\C=\frac{5}{10} \\\boxed{C=\frac{1}{2} }[/tex]
[tex]D=-6\times(\frac{-26}{12} )\\D=6\times\frac{26}{12}\\D=\frac{6\times26}{12}\\D=\frac{26}{2}\\\boxed{D=13}[/tex]
[tex]E=\frac{-9}{4} \times\frac{-5}{7} \times\frac{-28}{2} \\E=-14\times\frac{9}{4} \times\frac{5}{7}\\E=-14\times\frac{9\times5}{4\times7}\\E=-14\times\frac{45}{28}\\\boxed{E=-\frac{45}{2} }[/tex]
[tex]F=\frac{4}{5} +\frac{3}{5} \times\frac{1}{2} \\F=\frac{4}{5} +\frac{3}{10} \\F=\frac{8}{10} +\frac{3}{10}\\\boxed{F=\frac{11}{10}}[/tex]
[tex]G=\frac{-3}{4} \times(\frac{1}{5} +\frac{3}{10} )\times7\\G=\frac{-21}{4} \times(\frac{1}{5} +\frac{3}{10} )\\G=\frac{-21}{4} \times(\frac{2}{10} +\frac{3}{10} )\\G=\frac{-21}{4} \times(\frac{5}{10}} )\\G=\frac{-21}{4} \times\frac{1}{2}\\\boxed{G=\frac{-21}{8}}[/tex]
[tex]H=\frac{5}{26} \div \frac{15}{52} \:\:\:\:\: diviser \ revient \ a\ multiplier\ par\ l'inverse\\H=\frac{5}{26} \times \frac{52}{15}\\H=\frac{5\times52}{26\times15}\\H=\frac{260}{390}\\H=\frac{26}{39}\\\boxed{H=\frac{2}{3}}[/tex]
Bonne journée
