The interview was really difficult although the interviewer was nice. Got bunch of brainteasers and problems on probability stuff. No formal attire required and scratch papers available. Stuck on the probability question and did not get a second round.

The entire interview consisted of two mathematical problems. It was a conversational process of problem solving. The first question (as I am told) is almost always a more calculational probability problem, and the second focuses more on game theory. There may be no best answer - think heuristically to respond with at least something sensible.