Réponse:
A)
[tex] \frac{1}{3} - \frac{4}{3} \times \frac{2}{5} = \frac{1}{3} - \frac{4 \times 2}{3 \times 5} = \frac{1}{3} - \frac{8}{15} = \frac{(1 \times - 15) - (3 \times - 8)}{3 \times - 15} = - \frac{1}{5} [/tex]
B)
[tex]( \frac{1}{3} - \frac{4}{3} ) \times \frac{2}{5} = - 1 \times \frac{2}{5} = - \frac{2}{5} [/tex]
C)
[tex]\frac{1}{3} + \frac{4}{3} \div \frac{2}{5} = \frac{1}{3} + \frac{4}{3} \ \times \frac{5}{2} = \frac{1}{3} \times \frac{4 \times 5}{3 \times 2} = \frac{1}{3} + \frac{10}{3} = \frac{11}{3} [/tex]
