[tex] \dfrac{4}{6} \cdot( - \dfrac{3}{16} ) \cdot( - \dfrac{8}{5} ) = \dfrac{ \not4}{ \not6} \cdot \dfrac{ \not3}{ \not16} \cdot \dfrac{8}{15} = \\ [/tex]
[tex] \dfrac{1}{ \not 2} \cdot \dfrac{1}{ 4} \cdot \dfrac{ \not8}{5} = \dfrac{1}{ \not4} \cdot \dfrac{ \not4}{5} = \boldsymbol{\dfrac{1}{5} }[/tex]