Really? Comes once in zillion years ? Come on...
For this to happen, only 2 conditions need to occur...month starting on Friday, month having 31 days.
Probability of month starting on Friday is 1/7
Probability of month having 31 days is close to 1/2
The combined probability is 1/14...so the probability of having such a month in a year is 12/14!! Pretty close to 1
In short...May 2009 was such a month...LOL
