A man walks into a bar and says, Excuse me, Id like a pint of beer.

The bartender serves the drink and says, Thatll be four dollars.

The customer pulls out a twenty-dollar bill and hands it to the bartender.

Sorry, sir, the bartender says, but I cant accept that.

The man pulls out a ten-dollar bill and the bartender rejects his money again. Whats going on here? the man asks.

Pointing to a neon sign, the bartender explains, This is a Singles Bar.