In this tutorial the instructor explains the percentile formula. He says that the percentile formula is used to find the percentile rank of a data point in a group of data. He takes an example that consists of the lengths of puppies. Now he intends to find out the percentile rank of any puppy in the group. He shows that the formulate to compute a percentile rank of a particular puppy is rank R = 100 * (N< + (1/2)N= )/ Nt, where N< is the number of puppies whose length is less that the length of the current puppy and N= is the no of puppies with the same current length and Nt is the total number of puppies. He solves this example and shows how the percentile formula is used. In this tutorial the author shows how to find the percentile rank using the percentile formula.