Another classic:
Louie De Palma : Ignatowski! Where have you been all week?
"Reverend" Jim Ignatowski : I don't work weekends.
Louie De Palma : You been gone nine days!
"Reverend" Jim Ignatowski : Yeah...
Tony Banta : Jim, weekends are only two days.
"Reverend" Jim Ignatowski : Oh, I thought we'd switched to the metric system.