$\forall$$p$:FinProbSpace, $n$:$\mathbb{N}$, $X$, $Y$:RandomVariable($p$;$n$), $a$:$\mathbb{Q}$.
\\[0ex]rv{-}disjoint($p$;$n$;$X$;$Y$) $\Rightarrow$ rv{-}disjoint($p$;$n$;$X$;$a$$\ast$$Y$)