> Usually such a question is used not to fail you for not having the specific answer, but to observe your ability to reason about it and collaborate with the in

> Usually such a question is used not to fail you for not having the specific answer, but to observe your ability to reason about it and collaborate with the interviewer on pursuing the desired answer. What questions you ask, what resources you consult, experiments you perform, creativity you demonstrate, openness to alternatives, etc. Trivia questions like that are absolutely awful for demonstrating any of what you're talking about. There isn't any creativity involved. And it's not like the guy followed up with something like "where would you go to determine the answer?" There were 6 or 7 other interviews I went through that had interesting, open-ended questions that allowed me to bounce ideas off the interviewer and share my thought process. This particular interview was not one of them.