#### Answer

The point here is that we are essentially applying a hash algorithm to place the people in the group into one of 365 categories. The hash algorithm, of course, is the calculation of one’s birthday. The amazing thing is that only twenty-three people are required before the probability is in favor of at least two of the birthdays being the same. In terms of a hashed file, this indicates that when hashing records into 365 available buckets of mass storage, clustering is likely to be present after only twenty-three records have been entered.