There are 99 percentilesThe kthpercentile (Pk) is the value such that at least k percent of data are below the value and at most (100-k) percent are above that valueTherefore the kthpercentile(Pk) is a value in a data set that splits the data into two parts: The lower part contains k percent of the data, kis any number between 1 and 100. For example:•The 80th percentile is the value (or score) below which 80% of the observations may be found. •If a score is in the 86th percentile, it is higher than 86% of the other scores.Percentile

A class of 20 students had the following scores on their most recent test: 75, 77, 78, 78, 80, 81, 81, 82, 83, 84, 84, 84, 85, 87, 87, 88, 88, 88, 89, 90. What percentile is represented by 80?
What percentile is represented by 90?
Calculation of Percentile for given value - Examplek = (i / n) × 100

To calculate the
k
th
percentile (0 <
k
< 100), do the following steps:
Sort data set into ascending order array.
Calculate the location of percentile (index) by multiplying k percent
by the total number of values,
n
.
If the index is not a whole number, take next whole number (round
up). The corresponding value in your data set is the k
th
percentile.
If the index is a whole number, the
k
th
percentile is the average of
that corresponding value in your data set and the value that directly
follows it.
Calculation of value for given percentile
Is index decimal?
Roundup
Indexed value
Average of indexed and next values?
Yes
No
n
k
i
100

You have 25 test scores, and in order from lowest to highest: 43, 54, 56, 61, 62, 66, 68, 69, 69, 70, 71, 72, 77, 78, 79, 85, 87, 88, 89, 93, 95, 96, 98, 99, 99. Find P90and P20Is index decimal? Yes
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Percentile - Example