There were 2 different interviewers on the phone when they called. The interview started with the business oriented interviewer warming me up by asking basic mental math questions, starting off very easy and getting increasingly harder. After that they moved onto probability and statistics questions, most of them involving dice and decks of cards. I was then asked a variety of coding questions, mostly about what languages I had used and asked to explain differences and semantics between them. This was done by the more programming oriented interviewer. All in all, it was extremely difficult but I was not prepared for the type of questions they were asking.