How do you find the number that corresponds to Quartile 1, when given an even number of scores? If you have an odd number of data values {39, 40, 42, 44, 47, 48, 49, 51, 53}, what is the score that value that corresponds to Quartile 1? In general, I would like to know if you include the median's value (47) in figuring the position of quartile 1.

Quoting from Wikipedia:

> There is no universal agreement on choosing the quartile values.
>
> [...]
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> ### Method 1
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> 1. Use the median to divide the ordered data set into two halves. Do not include the median into the halves.
> 2. The lower quartile value is the median of the lower half of the data. The upper quartile value is the median of the upper half of the data.
>

>
> This rule is employed by the TI-83 calculator boxplot and 1-Var Stats functions.
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> ### Method 2
>
> 1. Use the median to divide the ordered data set into two halves. Include the median into both halves.
> 2. The lower quartile value is the median of the lower half of the data. The upper quartile value is the median of the upper half of the data.
>