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