1)

а)

[tex] \frac{2}{5} \times \frac{3}{7} = \frac{6}{35} [/tex]

б)

[tex] \frac{3}{4} \times \frac{5}{11} = \frac{15}{44} [/tex]

в)

[tex] \frac{2}{9} \times \frac{11}{7} = \frac{22}{63} [/tex]

г)

[tex] \frac{4}{5} \times \frac{6}{19} = \frac{24}{95} [/tex]

2)

а)

[tex] \frac{5}{7} \times \frac{7}{13} = \frac{5}{13} [/tex]

б)

[tex] \frac{4}{9} \times \frac{1}{4} = \frac{1}{9} [/tex]

в)

[tex] \frac{3}{8} \times \frac{8}{13} = \frac{3}{13} [/tex]

г)

[tex] \frac{3}{7} \times \frac{7}{11} = \frac{3}{11} [/tex]

3)

а)

[tex] \frac{6}{25} \times \frac{15}{17} = \frac{18}{85} [/tex]

б)

[tex] \frac{14}{15} \times \frac{4}{21} = \frac{8}{45} [/tex]

в)

[tex] \frac{24}{25} \times \frac{7}{36} = \frac{14}{25} [/tex]

г)

[tex] \frac{5}{24} \times \frac{16}{17} = \frac{10}{51} [/tex]