Grade School Cont'd: More Arithmetic

Thought you graduated? Well, you're almost there, but let's roll through some more arithmetic before you move on to bigger and badder things like conditionals. You know how to add numbers in Excel (if you're thinking: "I do?", then check out this post), now it's time to subtract, multiply, divide, and raise to powers.

In the addition post, we explored in excruciating detail the differences between using an Operator and a Function to accomplish your task. In this installment, we'll do the same for the other arithmetic activities in a less excruciating fashion. Download "Arithmetic" right here to start exploring.

Here is your Operators starting five:
+ Addition
- Subtraction
* Multiplication
/ Division
^ Raise to Power

Here is your Function starting four:
SUM Addition
PRODUCT Multiplication
QUOTIENT Division
POWER Raise to Power

If you've read any other posts, you'd probably assume I'm just going to talk about how awesome Functions are, and how they should be used in all cases to solve arithmetic problems. You would then be surprised to learn that in some cases Operators are actually better than Functions (even though it breaks my hear). If you take a look at the Arithmetic sheet, you'll see which functions are good, and which one is absolute garbage.

Before we close up shop on this brief post, here is a broad run-down of how arithmetic works in Excel, for those of you who haven't heard the term "Order of Operations" in more than twenty years. Order of Operations is PEMDAS, Please Excuse My Dear Aunt Sally, or whatever mnemonic you favor to remember that it goes: Parentheses, Exponents, Multiplication, Division, Addition Subtraction. Excel adheres to this rule and all of the other fun rules/properties you don't remember (associative, commutative, um . . .). Por Ejemplo:

(2+3)*4 = 20
2+3*4=14
(2+3)^2*4=100 (had to verify that one)

Things can get confusing with parentheses, because in addition to being used for mathematical operations, they also are involved in functions. So if you did some hybrid function, such as:

=SUM((2+3)^2,(3+4)*2)

Excel will solve it like this:

=SUM(5^2,7*2)
=SUM(25,14)
=39

Make sense? If not, play around in the worksheet and try out some different things. Remember, instead of using hard-coded numbers like I did here, do it using references as I do in the worksheet. Also, if the ideas aren't sticking, I recommend going back to the addition post, which really lays out the concepts underpinning this somewhat cursory explanation of arithmetic functions in Excel.