[tex]a) \ 1\dfrac{1}{2}\cdot\dfrac{2}{5} =\dfrac{3}{2}\cdot\dfrac{2}{5} =\dfrac{3}{5}[/tex]
[tex]b) \ 4\dfrac{1}{2}\cdot\dfrac{3}{4} =\dfrac{9}{2}\cdot\dfrac{3}{4} = \dfrac{27}{12} = \dfrac{9}{4} = 2\dfrac{1}{4}[/tex]
[tex]c) \ \dfrac{5}{7}\cdot2\dfrac{3}{4} = \dfrac{5}{7}\cdot\dfrac{11}{7} = \dfrac{55}{28} = 1\dfrac{27}{28}[/tex]
[tex]d) \ 2\dfrac{4}{5}\cdot3\dfrac{2}{3} = \dfrac{14}{5}\cdot\dfrac{11}{3} = \dfrac{154}{15} = 10\dfrac{4}{15}[/tex]
[tex]e) \ 1\dfrac{2}{3}\cdot2\dfrac{1}{7} =\dfrac{5}{3}\cdot\dfrac{15}{7} = 5\cdot\dfrac{5}{7} = \dfrac{25}{7} = 3\dfrac{4}{7}[/tex]
[tex]f) \ 3\dfrac{1}{4}\cdot1\dfrac{2}{5} =\dfrac{13}{4}\cdot\dfrac{7}{5} = \dfrac{91}{20} = 4\dfrac{11}{20}[/tex]
