Priority of Arithmetic Operations
Conventions that determine the order in which we operate when finding the value of a sequence of operations.
The order that we must follow is:
(1) Solve operations in parentheses (P)
(2) Solve exponents (E)
(3) Solve multiplication and division from left to right (MD)
(4) Solve addition and subtraction from left to right (AS)
A mnemonic device to remember this order is the acronym PEMDAS.
Example
[latex]\begin{aligned} 28 – 3(12 ÷ 4) – 4^{2} &= 28 &&– 3 × 3 &&&– 4^{2}\\ &= 28 &&– 3 × 3 &&&– 16\\ &= 28 &&– 9 &&&– 16\\ &= 19 &&&– 16\\ &= 3 \end{aligned}[/latex]