Screwed up the easiest brainteaser interview question ever

IB analyst interview (lateralling from small boutique to top MM bank). The interview's going great, I'm nailing all the finance/modelling-related technicals. Then I suddenly get hit with a "brainteaser" type question, and my nervous mind just goes completely blank. There's ten seconds of awkward silence before I admit I have no idea what the answer would be. When the VP explains the answer, I get red in the face as I realize how simple it was. No complex calculations, just basic logical reasoning. The interview continues and the VP remains friendly, but I'm visibly shaken. Did this completely ruin my chances? Should I address this in my follow-up/thank you email? Thanks

12 Comments
 

Ok since everyone's asking, here's what the question was:

If there's a tennis tournament with 3182 different players, how many matches will need to be played in order to determine the winner?

The answer is obviously 3181. If you just think about it for a second, you realize that a 4-person tournament would require 3 matches, a 6-person tournament would require 5 matches, an 8-person tournament would require 7 matches, and so on and so forth. x - 1.

But for some reason I immediately panicked and overthought things and started thinking in terms of factorials and other complex calculations, before realizing that that wouldn't make sense either, and then my mind just went completely blank and I gave up.

 

If it makes you feel better one time at a MM in NYC interview I got a brainteaser that Idk if I am stupid but I had to have the interviewer repeat it like 3 times lol and she straight up goes "This isn't that hard, I dont know why you don't understand it and why I have to repeat it so much". Safe to say I did not get the offer and right when I ended the zoom interview I almost cried lol 

 

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