“I really didn’t even put it together until we got pregnant,” he said in a telephone interview Wednesday. ’” Using a smartphone app, he said, his wife calculated a due date of Dec. “Hillary is exactly six hours older than me,” Luke Gardner said. “That comes out to .0000000751 -- seven zeros and then 751,” or about 7.5 in a million, he said, which comes to about one in 133,000.
Statisticians note that this ignores such factors as leap years and the fact that births are not evenly spaced throughout the year.
The probability that there are now no duplicate birthdays is (364/365)*(363/365)*(362/365). The probability that there are no duplicate birthdays falls below 50% when the 23rd person arrives. Indeed it is said that when they are used in court cases, even the judges draw the wrong conclusions.
It is common to hear that there is only one in a million chance of the DNA in the blood found at the scene of a murder matching that of the accused.
Add a third and the probability that he has a different birthday to the first two is 363/365.I had to break off the relationship because she wasn't faithful.Since then, I've always hated this day 'cos it reminded me of her.There is no such thing as proof positive, one can only prove a negative. If we were to invite people one-by-one to come into a room, ignoring leap years, it is possible to gather together 365 people all with a different birthday.Taking people at random in this way, one would have to select 366 people to be absolutely sure that two of them had the same birthday.