Percentile Rank, Decile, Ordinal Rank Calculator

Detailed Answer

Percentile Rank Formula

Rank = (P / 100) * N

Where,

P is Percentile,

N is Number of items

Decile Formula

Where,

L is lower boundary

F is cummulative frequency

f is frequency

N is total frequency

k = nth decile, where n = 1, 2, 3, 4, 5, 6, 7, 8, and 9

How to find percentile and ordinal rank ?

Example Question: Find out where the 25th percentile is in the below list.

Score Rank
30 01
33 02
43 03
53 04
56 05
67 06
68 07
72 08

Step 1:Arrange the data in ascending order

30, 33, 43, 53, 56, 67, 68, 72

Step 2:Calculate what rank is at the 25th percentile by using the following formula

Rank = P / 100 * (N)

Where P is Percentile = 25, N is Number of items = 8

Rank = 25 / 100 * (8) = 0.25 * 8 = 2.

The 25th percentile is the average of the values in the 1th and 2th positions (33 and 43 respectively).

The 25th percentile is (33 + 43) / 2 = 38

In this case, the 25th percentile score is 38, which makes more sense as its in the middle of 43 and 33.

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