From Scientific American
Math Explains Likely Long Shots, Miracles and Winning the Lottery
Why you should not be surprised when long shots, miracles and other extraordinary events occur—even when the same six winning lottery numbers come up in two successive drawings
By David J. Hand
What we think of as extremely unlikely events actually happen around us all the time. The mathematical law of truly large numbers as well as the law of combinations help to explain why.
With only 23 people in a room, the probability that two of them share the same birthday is 0.51—greater than 50 percent.
The Bulgarian lottery randomly selected the winning numbers 4, 15, 23, 24, 35, 42 on September 6, 2009. Four days later it selected the same numbers again. The North Carolina Cash 5 lottery produced the same winning numbers on July 9 and 11, 2007. Strange? Not according to probability.