Ceiling of x+m over n

Theorem
Let $m, n \in \Z$ such that $n > 0$.

Let $x \in \R$.

Then:
 * $\left \lceil{\dfrac {x + m} n}\right \rceil = \left \lceil{\dfrac {\left \lceil{x}\right \rceil + m} n}\right \rceil$

where $\left\lceil{x}\right\rceil$ denotes the ceiling of $x$.