00:01
We're given some data values, eight of them in total.
00:05
And let's organize them.
00:07
So we have 28, 25, 26, 15, 30, 34, 24, and 25.
00:19
So we know that our total number is n, 8.
00:23
But right now, how they're organized, this isn't super helpful.
00:26
So let's put them in order from greatest to least.
00:29
So we have 34 is the largest, then 30, 28, 26, 225s, 24, and a 15.
00:45
And this is helpful just so that we can kind of figure out some of these important pieces we're looking for.
00:52
The first one is we're looking for the range.
00:55
Well, the range is the difference in the greatest and the lowest numbers.
01:01
So the range is equal to the max minus the minimum.
01:11
So the range is equal to 34 minus 15, which means the range is equal to 19.
01:19
So there's our first important piece, just the difference in those two.
01:24
The second piece we have to find is the intercortile range.
01:28
So the intercortile range has to do with like the middle 50%.
01:33
Okay, the middle 50%.
01:36
And the way that we will find that is, is first you want to find out what our median is, the middle number.
01:43
And we do this by basically finding the exact middle, which out of eight numbers is actually pretty easy.
01:49
We find these middle two numbers, the 26 and the 25, and then we just take the average of those.
01:56
So we have 25 and a half.
01:58
That's our median, the middle number.
02:01
But the inner quartile range is we're asking for like the middle 50%.
02:06
So now we've got like the top four numbers, which would be like the upper, the upper half of our set.
02:16
And then we have the bottom one, which is like the lower half of our set.
02:19
And we want to find the median of those as well.
02:22
So let's look at the upper half first.
02:24
The median of just 26, 28, 30, and 34 is here.
02:29
It's right in the middle of 28 and 30, which is equal to 29.
02:36
So that's our upper quartile.
02:39
We call this q3.
02:42
I can write in a q3 here.
02:43
That's great.
02:45
The lower quartile is the opposite.
02:48
So we have 15, 24, 25, and 25.
02:50
So the lower quartile falls in between 24 and 25, which is 24.
02:57
Or 24 and a half.
03:01
And that's what we call q1, like quartile 1.
03:07
And the inter quartile range is just the difference between those.
03:09
So the inter quartile range, quartile range, is equal to 29 minus 24 .5, which is equal to 4 .5...