The blonde and her melons

This blonde was walking down a road, when this guy came along. The blond was carrying a bag. The guy goes, ''What are you carrying?'' She goes, ''Melons.'' The guy goes, ''Cool. if I can guess how many there are, can I have one of them?'' The blonde giggles and goes, ''If you can guess how many there are, you can have BOTH of them.''