Order of Operations
In mathematics the order of operations is a collection of rules that define which procedures to perform first, so that when we evaluate a given mathematical expression, we will all come up with the same answer.
1 st : Do any calculations inside p arentheses or other grouping symbols, starting with the innermost and working out.
3 rd : Work all m ultiplications and d ivisions, from left to right, as they appear.
4 th : Work all a dditions and s ubtractions, from left to right, as they appear.
So you don't get confused, remember PEMDAS which stands for Parentheses, Exponents, Multiplication-Division, Addition-Subtraction.
In California, we say P owerful E arthquakes M ay D eliver A fter- S hocks.
Do the operation in parenthesis first.
Then evaluate the exponent. Since the negative sign is inside the parenthesis, this means .
Multiply, and then add.
Be especially careful with problems like the following.
because parentheses come before exponents, BUT because exponents come before multiplication.
because parenthesis is the operation to start with.
Also, be careful with fractions. The fraction bar acts like a grouping symbol, so simplify the numerator and denominator first.
You can think of it this way: if you rewrote the fraction on one line, using the division symbol, you would need parentheses.