It is generally expected that you have a strong math background: calculus, linear algebra, differential equations, and statistics. I believe that the average GMAT score is 730, and most applicants will have stellar grades; you're good in these two categories, and it helps that you have two internships.
Oxford has a reputation for its extremely intense interviews. The questions asked will be very technical. After reading about the types of questions applicants were asked, I felt that I wasn't qualified for Oxford.
The Oxford MFE looks for applicants with specific skills. It's different from the MBA.
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