00:01
We've been given some test scores here of 19 students, and we want to find the intercortile range, the iqr.
00:09
So to get the intercortile range, we need to get the third quartile and the first quartile, and we need the difference between them, and that's the intercortile range.
00:19
So how do we find these? so you need to put your data in order, so that's your first job.
00:26
And to get the quartiles, we need a particular data point.
00:30
The first quartile is found at n plus 1 over 4.
00:38
And the third quartile is 3, n plus 1 over 4.
00:48
So here we have 19 points of data.
00:51
So when they're all in order, the fifth piece of data will be the first quartile and the 15th piece of data will be the third quartile.
01:02
So let's do that.
01:03
So our smallest piece of data is 43, and i'm going to count up from smallest to largest.
01:11
When we hit the fifth, we have the first quartile...