Here is my data set: 5, 8, 12, 42, 43
I am trying to work out the first quartile. When using R (the programming language) it shows the 1st quartile as 8, but when I work it out manually, it shows it as 6.5.
Here's how I am working it out:
First I work out the 25%
25/100 * (5 + 1)
There is no value at 1.5, so I do the following to get the average:
(5 + 8) / 2
Where am I going wrong?