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Ok in this video I am going to show you, we are actually going to take a look at what
an outlier is and then I just want to do the mean again and the quartiles because this
set of data actually has an odd number so it will just be a little bit different and
then that way you will have an example of both where there was an even number and an
odd number. But again, first we need to sort our data. So highlight, go to sort and filter
and then sort smallest to largest. Now look at that data set. Is there any number that
is really really different from the others? I am hoping that you looked at it and said,
"Oh 20 is REALLY different from all the others!" That's an outlier. And so in this case, 20
is going to be an outlier. It actually will have an affect on the mean. Let's take a look
at that real quick. If I find the mean with 20 in it, so =average, let's take the average
of all those numbers. And then right below it, let's take the average but this time it's
going to go A2 - A17. Don't forget your = it's really important. Now, everything except A1.
And notice what happened? So, it pulled it down from 75 to 71 just by having that 20
in there. So, I wanted to make sure you guys saw that. Alright, now let's do the median. =median highlight all the data
values, close parenthesis, A1-A17 and our median is 75 which since there are 17 data
values I'm betting 1, 2, 3, 4, 5, 6, 7, 8. I'm betting it's this one I am actually going
to go ahead and highlight it or fill it in so that that way I don't forget that's the
one that's exactly in the middle. If you count there are 8 above it and 1, 2, 3, 4, 5, 6,
7, 8 below it. So let's find the first quartile. It is going to be the median of the lower half of the data so
A1 - A8, notice not including that median and it is 63. And then the third quartile
is the median of everything that is above the median of the data set.