Can a BA in Economics graduate apply to a MBA in Finance program? Is it easy or difficult?
- answers

Yes you can
I received a BS in Economics in December 2010 and have been working on an MS in Finance since then. I did take basic courses in accounting and finance but I think they would have accepted me anyway. If you don't have any basic accounting or finance you may have to take a prerequisite or two. For an MBA you may also have to take a prereqs in marketing and business psychology depending on the program.

I will not claim to be an expert in business or business related education programs, but I am fairly sure that a BA in Economics is a sufficient enough degree to prepare you for moving into an MBA in Finance Program.
As for the difficulty level, for that I am going to refer to an articles that will help you prepare applying to an MBA program - Preparing for Online MBA Prerequisites - Tips for Success.
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