Hal and Carol accept an invitation ... party. Hal sees that there will be 30 people attending the party and says to Carol, “I bet you $100 that at least two people will have the same birthday ...

Last year, Roberts wrote a simple birthday invitation without pictures and designs for a casual party in her backyard. The kids had fun running through a makeshift obstacle course, playing in the ...

The Weekend Edition Saturday Math Guy ... two of them have the same birthday? (It's more than half!) The birthday problem asks how many people you need to have at a party so that there is a ...