To start i will say that i am an engineering major, i've heard engineers have an easier time with the case studies due to the fact that we are good with math and problem solving.
After the company reviewed my resume, through my University, i was invited to take an online assessment. The online part was very easy, basic algebra and graphs, SAT type math. Afterwards, was given a 1on1 interview at my particular University. The first 1on1 is a case study, the case study was involving credit card type problems, and involves statistics and algebra, as well as basic knowledge of what might make a company more money (eg. increase profit, decrease costs).
After this, i was invited to Richmond for a number of interviews. Of the 12-15 people there i believe only around 3-5 of us got an offer. 2 case interviews and a behavioral interview in the morning. The cases were decently challenging, but they aren't expecting a perfect score, just that you show good insight, and great problem solving skills. A nice tour of the campus and free lunch, then they invited 3-4 of us back for a interview in the afternoon.
The afternoon interview was with a VP of the company, it showed how much the company cared that they sent someone that high up to interview us, just to make sure we really would help the company. The last interview is again a case interview, and was around the same difficulty as all the others.
I was told in an extremely short amount of time that i had passed and was extended an offer to join the company.