Răspuns:
[tex]1 \times \frac{1}{4} \times \frac{6}{7} \div \frac{15}{28} = \frac{1 \times 4 + 1}{4} \times \frac{6}{7} \div \frac{15}{28} = \frac{5}{4} \times \frac{6}{7} \times \frac{28}{15} = 2[/tex]
b)
[tex]1 \times \frac{1}{8} \div \frac{3}{4} \times \frac{2}{15} = \frac{9}{8} \times \frac{4}{3} \times \frac{2}{15} = \frac{1}{5} [/tex]
c)
[tex] \frac{20}{27} \div \frac{5}{9} \times 3 \times \frac{3}{7} = \frac{20}{27} \times \frac{9}{5} \times \frac{24}{7} = \frac{32}{7} [/tex]
d)
[tex]1 \times \frac{7}{15} \times \frac{10}{11} \div 1 \times \frac{7}{9} = \frac{22}{15} \times \frac{10}{11} \div \frac{16}{9} = \frac{22}{15} \times \frac{10}{11} \times \frac{9}{16} = \frac{3}{4} [/tex]
e)
[tex]2 \times \frac{11}{12} \times \frac{9}{5} \div 7 \times \frac{7}{8} = \frac{35}{12} \times \frac{9}{5} \times \frac{8}{63} = \frac{2}{3} [/tex]
f)
[tex] \frac{25}{42} \div 3 \times \frac{1}{3} \times 4 \times \frac{2}{3} = \frac{25}{42} \times \frac{3}{10} \times \frac{14}{3} = \frac{5}{6} [/tex]
