Heard this from a D.J.:

A guy walks into a bar. He sees an attractive person of the opposite
gender and walks up to her. He said, Hey, can I buy you a drink?
The gal stands up walks to the middle of the room and shouts, WHAT
DO YOU THINK I AM, A PROSTITUTE? She storms out of the bar, and the
guy, face completely red, orders a beer and sat in a dark corner. A
few minutes later, the girl returns and came up to the guy. She says,
Im sorry about that. Im psychology major and I was just testing to
see your reaction to what I just said. Then the guy stands up and
walks to the middle of the bar and shouts, FIFTY DOLLARS? 🙂