>Or maybe 'What is 6 x 7?' :o)

That's another Adams' trick... somewhere in the Golganfrinchan episode, the question does appear as 7 x 9, and he deliberately doesn't give his characters any lines regarding the arithmetical issues. Some fans actually looked for a numeric base where 7 x 9 would actually be 42, but 7 x 9 # 42 in any of them.