The first blonde tells the bartender, "I'll have a BM."

The bartender taken back asks, "A what?"

She says, "A Bloody Mary, Duh."

The second blonde tells the bar tender, "I'll have a JC."

Again, the bartender asks, "What is a JC?"

She responds, smacking her lips, "A Jack Daniels and Coke, Duh!"

The third blonde, asks the bartender for a "fifteen". The bartender is really puzzled now and asks her what this means.

The third blonde shakes her head and says, "Of course, its a seven and seven, Duh!"