Droids "shooting the bull"

C-3PO: Okay R2, calculate the odds of a brawl between Vador and let's say...Chewy and 10 Ewoks.

R2-D2: Tweet - Chirp - Chirp - Tweet

C-3PO: How am I suppose to know if the Ewoks are carrying lightsabers? It's a hypothetical question you box of lug nuts!