Capital One Statistician interview questions

I was given a case study. They are selling a credit card. They provide you all the costs, and their questions was to find the break even point

Case study, not like consulting firm, more numeric, I like the case study, very basic math, I jumped to the question too soon, should have communicated more with the inerviewer, anyway this was the first time I did case study, the interviewer and recruitment lady are very nice and friendly, feel it's a good company to work for.