Réponse:

Bonsoir,

[tex]a = \frac{5}{4} + \frac{11}{4} \times \frac{20}{33} = \frac{5}{4} + \frac{220}{132} = \frac{5}{4} + \frac{55}{33} = \frac{5}{4} + \frac{5}{3} = \frac{15}{12} + \frac{20}{12} = \frac{35}{1} [/tex]

[tex]b = \frac{1}{12} \div (2 - \frac{3}{7} ) = \frac{1}{12} \div ( \frac{14}{7} - \frac{3}{7} ) = \frac{1}{12} \div \frac{11}{7} = \frac{1}{12} \times \frac{7}{11} = \frac{7}{132} [/tex]

[tex]c = ( 1 + \frac{2}{3} )( \frac{12}{5} - 2) = ( \frac{3}{3} + \frac{2}{3} ) \times ( \frac{12}{5} - \frac{10}{5} ) = \frac{5}{3} \times \frac{2}{5} = \frac{10}{15} = \frac{2}{3} [/tex]

Bonne soirée, j'espère t'avoir aidé