Nielsen Professional Services, interview questions

I dropped my resume through my university career service as well as through the Nielsen careers site. A week after the resume drop deadline, I was contacted for a first round interview, consisting of a behavioral and a 2hr math/writing test. The test was what I would say, probability, finite, and business math problems with some writing questions as well. The writing portion asked to write a letter stating bad news to a CEO, nothing too difficult, just assessing business writing skills. I completed the exam and then went to my interview. The interview was pretty standard and the lady that interviewed me seemed genuinely interested in my story. Normal, tell me about yourself, major, why do you want to be at Nielsen, how did you first hear about Nielsen and additional questions, format. About halfway through the interview they asked me to advice a client that was debating on where to invest his money. I would consider this a mini case, mostly focusing on your logic and points (there was no 'right' answer). I didn't hear back from Nielsen for over a month. I knew some of my friends had received rejection letters so I decided to email my interviewer. The next day, she emailed me back and the day after I got a phone call extending me an offer.