As strange as it may sound, in a group of 23 people, the odds are greater than even that someone else in that atleast 2 of them have the same birthday. Doesn't quite sound right to me but there you go.
How does this relate to engineering? It doesn't really except to illustrate that probabilities aren't always what you might expect.
"A good scientist is a person with original ideas. A good engineer is a
person who makes a design that works with as few original ideas as
possible" - Freeman Dyson