For example, if your set of numbers is [3, 4, 5, 11, 3, 12, 21, 10, 8, 7], you would reorder them like this: [3, 3, 4, 5, 7, 8, 10, 11, 12, 21].
For example, the set [3, 3, 4, 5, 7, 8, 10, 11, 12, 21] has 10 numbers.
For example, if there are 10 numbers in your data set, your formula will look like this: Q3=34(10+1){\displaystyle Q_{3}={\frac {3}{4}}(10+1)}.
For example:Q3=34(10+1){\displaystyle Q_{3}={\frac {3}{4}}(10+1)}Q3=34(11){\displaystyle Q_{3}={\frac {3}{4}}(11)}
For example:Q3=34(11){\displaystyle Q_{3}={\frac {3}{4}}(11)}Q3=814{\displaystyle Q_{3}=8{\frac {1}{4}}}So, the upper quartile is given by the number at the 814{\displaystyle 8{\frac {1}{4}}} position in the data set.
For example, if you calculated 12 using the formula, then the upper quartile is the 12th number in the data set.
For example, if you calculated 814{\displaystyle 8{\frac {1}{4}}} using the formula, then the upper quartile is between the 8th and 9th number in the data set. In the set [3, 3, 4, 5, 7, 8, 10, 11, 12, 21], 11 and 12 are the 8th and 9th number. Calculate 11+122{\displaystyle {\frac {11+12}{2}}} to find the average:11+122{\displaystyle {\frac {11+12}{2}}}=232{\displaystyle ={\frac {23}{2}}}=11. 5{\displaystyle =11. 5}So, the upper quartile of the data set is 11. 5
For example, you might enter the data set [3, 3, 4, 5, 7, 8, 10, 11, 12, 21] into cells A1 through A10 in the spreadsheet.
For example, if you want to find the upper quartile of cells A1 through A10, your function will look like this: =(QUARTILE(A1:A10, 3)).
Note that with the release of Office 2010, there are two different quartile functions: QUARTILE. EXC and QUARTILE. INC. These functions cannot be used in earlier versions of Excel, and QUARTILE can still be used. The two Excel quartile functions use a different formula to calculate the upper quartile. QUARTILE/QUARTILE. INC uses the formula Q3=34(n−1){\displaystyle Q_{3}={\frac {3}{4}}(n-1)}, and the QUARTILE. EXC function uses the formula Q3=34(n+1){\displaystyle Q_{3}={\frac {3}{4}}(n+1)}. Both formula are accepted ways to calculate quartiles, although the former is becoming standardized in statistical software.
