How to do basic math formulas and calculations in Excel 2007, Excel 2010, Excel 2013, and Excel 2016

all right in this video we're going to talk about doing a basic math in Microsoft Excel this is going to be the first in the series of doing math formulas and functions in Microsoft Excel I'll have uh about six or seven videos that I'm going to make this week on that topic so let's start right away with the basics here uh as you see over here rule one all mathematical formulas in cells start with the equal sign so let's do a simple example if I say = 2 + 3 all right notice how the formula definitely starts with the equal sign and when I hit the anarch key it's going to give me the result uh when I click on that cell the formula is up here in the formula bar so I can change the formula up there in the formula bar and the and the cell is going to show the result of the formula of course so let's try that again um equals 78- 35 and it's going to give me the result of 43 when I hit the an k rule number two you can type in a number or click on a cell that already has the number you want to use so let's say I want to use the 43 in my formula so I could do it one of two ways I could say equals 43 plus 17 I can do it that way and I'll get 60 or since the the number 43 is already on my spreadsheet I'm going to say equals and then click on that cell that has the 43 which happens to be B2 + 17 now here's why I do it that way notice how right now they have the same result but look at this formula this formula says equals B2 + 17 that means use the number that's in cell B2 the reason that that I'm doing it that way is let's say if uh if uh B2 changes to uh 74 because that changes then A4 also changed because A4 has a formula that says equals B2 + 17 so in B2 changes A4 is also going to change okay uh so that's that's what rule two means you can type in a number or click in a cell that already has a number you want to use now rule three Excel does this math using the mathematical order of operations not just left to right so let's try a longer formula now let's do equal = 5 + 4 * 3 so if you take it left to right then we'll take 5 + 4 = 9 * 3 is going to be 27 okay so let's see what the Excel really gives us it really gives us 17 because what happened was we took the it did the 4 * 3 first which is 12 plus the 5 which is going to give us was to 17 uh now because it did it in the mathematical order of operations the mathematical order of operations is down here this is the actual order so anything in parentheses is going to be first anything with exponents is going to be next expon means uh like 2 to the 4th power if you look at this example over here equals two up Arrow 4 means two to the fourth power so that's what I mean by exponents multiplication is next in the mathematical order so here's an example multiplication equals 5 time 6 where the asterisk is the multiplication of course that will give you 30 division is next in the order so here's an example of division equals 75 / 5 where the slash is the division it's going to give you 15 uh and then addition is next in the order and then subtraction so uh it goes parentheses exponents multiplication division addition and subtraction now there's actually a phrase that helps you remember the order and this is something I learned a long time ago and maybe you learned this as well maybe back in algebra class right no not algebra class I'm just saying that's maybe where we learned this um this is where I learned it so think about the first letter of each of these words p m d a s right down the row there and then the pneumonic or the Phrase That Pays is please excuse my dear Aunt s maybe maybe you remember that from a long time ago so it really helps you remember the order of operation so when you have a longer calculation um it's not going to take them left to right it's going to take them in the order of mathematical order of operation so let's see this formula and how you can change it with the parenthesis I'm going to put a parenthesis before the five and I'll put a parenthesis after four so now because of the mathematical order it has to do the things in parentheses first therefore it'll do the 5 + 4 first and then that's going to give us the 27 you see you see the difference that the parentheses made before it was doing the multiplication first because of the mathematical order so I had 17 but now it's doing the arithmetic first because of the um because of the parentheses let's try another example like that if I say equals 7 + 5 / 15 - 2 * 4 now I don't know what that's going to give us uh but I'll tell you how it's going to do the math it'll do the division first then it'll come over and do the multiplication then it'll come over and do the addition then it'll come over and do the subtraction so in this case it gave me negative uh this is actually -2/3 okay basically is what it came out to so let's make it have a different number now I'm going to come up here and uh we'll do the addition first then we'll come over here and we'll do the uh the the subtraction so I want the addition to happen first here then the subtraction then I want the 7 + 5 that total to be divided by the 5 - 2 and then uh divide the whole I mean multiply the whole thing by four and now you can see I have a different result so you actually have control over the order because of the um because of the mathematical order and because of the parenthesis now look at rule number three and this is kind of a good example of this your formula can be any combination of numbers cell references built in functions and mathematical operators and it could be as long as or as complicated or as simple as you need to be so that's a pretty good example it's starting to be pretty compc complicated there uh in another video this week in this series we'll have uh we'll have some of the built-in functions but let me give you one of the built-in functions that people use all the time if I use 23 40 uh 34 45 65 42 if I were to add those up we could say equals right all formul start with the equal sign and then you can type in sum and uh now that's a built-in function and I'm going to show you where there's many many more functions in the next couple videos but these functions will require parentheses and now it's looking for a bunch of numbers to add up so I'm just going to highlight these numbers over here and then I'm going to close that uh parentheses so it says equal sum open parentheses C6 colon C10 by the way you would read the colon as through so I would say C6 through C10 close parentheses and that'll add up those numbers let's take a look at that formula equals sum open parentheses C6 through C10 closed parentheses so if I change any of those numbers I want to change the 23 to 67 and then watch the total at the bottom it recalculates because that's how Excel does its math if any of those cells in that formula going to change the form will recalculate and that's why you do it that way uh so we could do a sum like that now I'm going to delete that cell in that case I just typed that in right but here's really a quicker way to do a sum especially you have a column or a row of numbers this is called an auto sum follow my mouse first of all you're going to click on the cell where you want the sum to appear and then you're going to pick on the home menu and then you're going to come way over here and you're looking for this one that says Auto sum that's exactly what it's going to do for you if I pick on the auto sum usually I guess is properly what you want to add up in in this case it did see see I'll put the same exact format that I had typed in equals sum open parentheses C6 through C11 this time Clos parentheses which is fine so in that case you can type in the sum formula or you can use the auto sum uh just like that it's going to give you the same kind of result so let's um let's try a different formula I could say equals this plus this number Plus this number minus this number times 5 so this is a combination of using um the cell references and then just a normal number now let's say I wanted one of the additions that happen first so therefore I'm going to click on the formula and then put in the parentheses where I want things to happen first you see and that that follow follows along with the mathematical order of operations where let's see what happens if I didn't have the parentheses I'm just going to go back and change the formula up here on the formul the bar okay so you can see that sometimes the for the parentheses make a difference but that's how you have control over what's going to happen first you can use your parentheses to give things a priority uh so here's the four rules for Excel formulas all formulas start with an equal sign you can see that's going to be the case on all the cells that actually have a formula rule two you can type in a number or click on a cell that already has the number you want to use so in this case uh if we say equals this equals A2 + B2 that's what we mean by the cell references so uh now you can either point to those cells with and click on them or you can p into them with your keyboard arrows like that or you can just type in the cell reference but that's what rule two means and you can see how that's going to work rule three Excel does this math using the mathematical order of operation so on a longer calculation like this if I didn't have the parentheses here it would have done the the multiplication first because that's the mathematical order but by using the parentheses I'm telling it to do the addition first because notice how the parentheses anything in parentheses is going to happen first because of the mathematical order uh so that's rule three and then rule four your formula can be any combination of numbers cell references built-in functions and mathematical operators and it can be as long and comp complicated or as simple as you need to be like this one over here or this one over here has um the parentheses plus it has cell references plus it has numbers and it has other mathematical operators so in that case it's going to do the thing in parentheses first then it'll actually come over and do the multiplication then the addition then the subtraction and you can see it has combinations of cell references and numbers so that would be a good example of rule number four and this should start to give you uh an idea of how to do basic math in Microsoft Excel uh so we'll look look for more videos uh on this topic uh coming out this week