Task 5: Birthday Problem

• Itzik Ben-Gan has in his books one of the most interesting logic puzzles based on different questions like this one:  " What’s the probability that in a group of 23 randomly chosen people, at least 2 of them will have the same birthday? ".

• The answer is impressive and might seem strange. " Most people intuitively assume that the probability is very low. However, the probability that two people in a group of 23 have the same birthday happens to be greater than 50 percent (about 50.7 percent). For 60 or more people, it’s greater than 99 percent (disregarding variations in the distribution and assuming that the 365 possible birthdays are equally likely). The tricky part of the puzzle is that you need to determine the probability that any two people share the same birthday—not a specific two. "

For the exact solution and some interesting information about the birthday paradox, check
out the Wikipedia entry.