 So let's take that same equation we were just talking about in what is a table and let's apply it Let's actually use it inside of Excel So right now we can take a look and we see that same grid like structure I was just referring to we see that we have the a column b column c column all our verticals have a column all Of our horizontal rows also have numbers well The first thing we did was we started by entering in some text now in a one for example I'll just put in the word subtotal now when I hit enter That's all I get is I get Subtotal that's because this is considered text text is a little different than a math equation a cell reference for example, if I wanted to refer to the a Column you know I will we'll get to that in just a second But I that a is it you know that a is not text that a for the a column is a little different Then we put in tax and total Now one thing you'll notice is that I'm highlighted currently on a for a for is my active cell If I want to move that well, here's the luxury of the grid like structure. All I have to do is click Now again, we said that we're going to put in a tip calculator So I'm going to put in the dollar sign 1250 and then I said 7% Now again, this is where we have to deal with a math equation if I just take my cells B1 and B2 and I put them in here B1 times B2 Nothing happens, you know, it's it's because it's Inferring that what I just did was I typed text now even though it says B1 Well again, how is that any different than this to the computer? It's not so we have to introduce That equals sign that equals sign tells Excel you are about to do a math equation Now if I do B1 notice what happened it highlighted B1 It's in a little color coding effect to just kind of give me a visual representation of what Numbers I'm going to be working with now. I said that I can't just multiply By B2 88 cents. That's not That's not the price of what I had to pay. I wish but that's not how it works Instead we start by saying B1 B1 is my base my starting point if you will and then I included PIMDOS Please excuse my dear and Sally I added in some parentheses now the parentheses basically are going to be Evaluated first Just because I put in B1 before doesn't mean that I can't put it in a second time This is algebra all over again. I can throw x everywhere, you know x a x squared plus b x plus c Oh god, he's no, I'm remembering the hardships. No, that's what we're doing is I'm just saying I need to take that 1250 and I need to add the extra to it That 7% again instead of me hard coding that in B2 Close my parentheses and as soon as I hit enter what I should see is 13 38 Excellent the reason why we do this though is because now what's happening is Excel's evaluating B1 and B2 if I change B2 for example say I don't know Economy still bad sales tax goes up to 10% if I hit enter Notice what happened? my total changed if For example, my subtotal was a little less 19 or 999 as soon as I hit enter I can see all of a sudden the calculations unfurl