Let $M = (X, \mathcal{F}, \mu)$ be a D1158: Measure space such that

(i)	$E, F \in \mathcal{F}$ are each a D1109: Measurable set in $M$
(ii)	$E \subseteq F$ is a D78: Subset of $F$
(iii)	\begin{equation} \mu(E) < \infty \end{equation}

Then \begin{equation} \mu(E \triangle F) = \mu(F) - \mu(E) \end{equation}