Addition and multiplication works both ways, as we see below:
\begin{align*}
\overbrace{454 + 2324}^\text{add these first} + 4352 &= 2778+4352 \\ &=7130 \\
454 + \overbrace{2324 + 4352}^\text{add these first} &= 454+6676 \\ &=7130
\end{align*}
and
\begin{align*}
\overbrace{3747 \times 32848}^\text{multiply these first} \times 27748 &= 123081456 \times 27748 \\ &= 3415264241088 \\
3747 \times \overbrace{32848 \times 27748}^\text{multiply these first} &= 3747 \times 911466304 \\ &= 3415264241088.
\end{align*}
We see we get the same answer in both cases. Since this happens in general, both $+$ and $\times$ are called associative binary operations.
Subtraction and division are not associative binary operations. For subtraction, the convention is to subtract from left to right.
\begin{align*}
\overbrace{4773 - 3944}^\text{subtract these first} - 38482 &= 829-38482 \\ &=-37653
\end{align*}
which is the correct answer. If we want to subtract the other way, we add brackets, such as:
\begin{align*}
4773 - \overbrace{(3944 - 38482)}^\text{subtract these first} &= 4773-(-34538) \\ &=39311
\end{align*}
For division, we simply would not write $82794 / 23484 / 2394$, since it's ambiguous. We would add brackets in either case:
\begin{align*}
\overbrace{(82794 / 23484)}^\text{divide these first} / 2394 &= \tfrac{13799}{3914} / 2394 \\ &= \tfrac{13799}{9370116} \\
82794 / \overbrace{(23484 / 2394)}^\text{divide these first} &= 82794 / \tfrac{206}{21} \\ &= \tfrac{869337}{103}.
\end{align*}
