Hi rfg123,
You can still apply to Haas and other schools without explicitly meeting their expected requirements for quantitative coursework. However, it would be in your best interest to take those courses before applying. It will make your candidacy stronger (especially since you have an undergrad degree in the arts). For example, on my own initiative, I took Calculus, Stats, and Economics in preparation for my application to HBS. Then, once I got in, they required that I take Corporate Finance and Accounting and earn a B+ or better in each. Believe me, it is much better to take these courses when you have plenty of time to rather than to have to rush and take them like I had to do with Corporate Finance.
You can take courses like Stats, Corporate Finance, and Accounting through BYU's online program, at your local community college, and through fancier (read: more expensive) more prestigious institutions as a non-degree-seeker as well.
UCLA Anderson has a great list of places to take pre-MBA quantitative coursework:
https://www.anderson.ucla.edu/x459.xml#5
Also, HBS offers online modules that are very helpful as well (not going to count as a real course though):
https://web.hbr.org/store/landing/courses/index.php
You have no need to freak out! Continue working on your application and see which courses best fit your knowledge gaps you hope to fill, your learning style, and the time you are willing to put in them.
I suggest (in this order):
1) Stats
2) Accounting
3) Corporate Finance / Intro to Finance
I suggest the Stats more for the AdCom (for immediate practicality, I would highly suggest Accounting over Stats if you are only going to take one).
Good luck!
Kaneisha
Harvard Business School MBA 2010, Harvard Kennedy School MPA 2010
Founder, The Art of Applying
Admissions Consulting for MBA, MPP, Joint Degrees, and Fellowships
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