 It picks it picks that up not exactly the way I would have had it on the bottom, but that's fine plus and then X To the end To the end Boom. Oh See it didn't like so now it says plus X minus in so I'm gonna say erase that What are you thinking? Maybe it didn't like that X. Maybe it's plus is even wrong. I'll make plus X in all right that looks good, and then I'll put this whole thing over Underline on in So this is this is for Now the X was on top So I actually erased it and then I made a very large X bar on the left-hand side So now it's properly picking up the X bar which is standing in for the mean or the average the mean or average often being shown in the symbol of X bar or Mu which is the Greek letter looks like a you is the Greek letter Mu and it might differ depending on whether we're talking about the entire population or a sample of the population We'll get into more of that in future presentations But the average calculation then is going to be X one plus X two plus X three and so on and so forth up to X in in Representing the number of items in the population the number of X's all of that divided by then in Representing the number of items in the population so I can go ahead and say that that looks good So let's insert it So we'll just insert down here and there is our formula now once made I can go to the Home tab over here and increase the font if I so choose so we might want to make a larger formula and Sometimes it might wrap it so if this gets too small it could kind of mess up the formula So you have to make sure that your font size Lines up with how large the box is so it's being represented properly and I'll type mean Calculation up top I'm going to select the entire worksheet and go to the home tab Fonts group and make it bold. Let's actually format the worksheet like I normally do as well So I'm going to right-click on the worksheet Format and then I'm going to make the entire worksheet is going to be numbers I'm going to go into the numbers group and then I usually go currency negative numbers bracketed and red No dollar sign. I don't need any decimals So I'm going to say okay, and then I'll make this my header. I'll make this black and white home tab Fonts group. It's kind of like the title so maybe black and but we'll do that black and white on the header now notice This obviously is on top of the cells It's not within the cells so you're gonna have to kind of be careful and move it around When I select a column this isn't selected when I select the column Generally, it's kind of attached possibly to a particular cell that it's in but it's not really it's it's not attached to these columns for example You can also copy this if you wanted to Copy it and you could paste it As an image and that could be a useful tool if you wanted to paste it somewhere else So you don't kind of mess up the formula that kind of makes it almost hard-coded in a sense So that it's so you can't go in there and type in it You can see through it here So the other thing that that you could do is you could put some formatting around this so that there's a Fill color so I could make a shape fill and make it white so that now It's you don't see the background of it. The other way you can do that is actually make the cells behind it White I can go to the home tab font group and make the cells behind it white And so now it's it doesn't you can't see the grid lines in the back of it, but it's probably better I'm now that I'm working with this I'm gonna control Z or undo to make to make the actual box white or some other color you can make it So that it stands out as its own as its own thing, right? Maybe orange isn't too bright. So something like that. Maybe so let's do another one I'll do another formula This is another way that we can express the mean and we'll talk about other formulas in the future And this is so so we'll practice this as well in the future, but let's insert another equation And so here's my equation thing. I'm gonna go into it now. I have the equation up top I'm gonna make an ink equation again and just type this one in so this one So we're gonna represent the mean in a different way So I'm gonna start with X bar again this time. I'm gonna type it really large I'm gonna say this is gonna start with an X on the left So it knows that that's on the left. It's gonna be an X bar So pick that up properly and then I'm gonna say equals go somewhere in the middle here equals So there we have that and then I want this some Symbol so the some symbols gonna look like this did Yeah, and so I picked that up then I want an end on top the end sometimes it doesn't pick up until I do the bottom bit So it didn't really see it yet, but I'm gonna say that's okay. I'm gonna say let's put an eye dot equals One so then it saw that and then it picked up the end so that looks good on this side. I want to say X and Then to I sub I And so it picked up a J instead of an I Let's erase that. Let's see if I can erase just that and then say no it needs to be an eye So there it goes. So now it picked up an I so I think that's right And then this whole thing needs to be over. So I'm gonna underline it and then in And on the bottom Boom so there it goes so it formatted so now instead of putting the end like on top it put it a little bit off to the side So that's fine. So we'll keep that that looks good So now what this is basically saying is we're gonna it's another way to express this right? This is the sum function. We want to sum all of the X's X sub I Where we're going to be implementing X starting at one and keep on summing up all the X's until We get to the number of X's to be subbing in there Which is in Represented here and then take that whole thing that we summed up and divide it by the count Which is in so this is another way that we can express it That's going to be once again the mean or like the average. So let's insert it. So there we have it so I'll pull this down here and Let's make this orange on the fill again and this how big was this one this one was like 24 so let's make this one 24 as well. So we'll bring it on up to 24 So there we have it. So that's nice Now the next thing we might want to do is say well How can I represent some of these items in Excel like an X bar for example? How might I do that? One way you could do the X bars you can type in an X and you can go into the insert tab up top and Then in the symbols we're going to go into the symbols here Now when you're using these symbols often It's useful to go screw all the way up top to this on the left the font It's just being the normal text font and then I want to combine this X with something else the bar on