Răspuns :
[tex] \frac{7}{5} \div \frac{1}{4} = \frac{7}{5} \times 4 = \frac{28}{5} \\ \frac{7}{3} \times \frac{6}{5} = \frac{14}{5 } \\ \frac{2}{9} \times 3 = \frac{2}{3} \\ \frac{4}{5} \times 10 = 8 \\ \frac{8}{15} \times \frac{5}{4} = \frac{2}{3} [/tex]