hey buddy, don't worry about asking 'noob' questions - everyone starts somewhere.
For you, it's not going to be about getting good grades and all that for b-school. The biggest challenge for you will be - why MBA? Think about it. AdComs view thousands of these applications every calendar year and there are so many potential applicants who can be just as successful as the next one. Then all of a sudden, adcoms pick up an application that has a JD on it. What would be their reaction? I think the first thing they're going to think about is "why is this guy wanting an MBA when he/she already has a JD?" "If the JD wasn't what he/she wanted, why in the world did he/she go for it and complete it?" These questions then lead to how an applicant may not be as focused (career or life) as the other person who went to BYU for undergrad, worked at JPMorgan for 4 years, then applied to business school to transition into a life as a consultant. Do you see what I'm saying here? So the hardest thing for you is to explain your reasonings behind getting a JD.
Former corporate law, 3.5 GPA, and a decent GMAT score are key combinations to business school. As long as the applicant is able to clearly articulate why he/she needs an MBA at this point in life. I know doctors who are going back to get an MBA, but they're certainly a minority (perhaps by choice, not selectivity). And even with those numbers and experience, a lot of it has to do with luck as well. Again, you're competing with not just hundreds of applicants who are applying to top b-school every year, but thousands and thousands (Harvard's inching ever closer to 10,000 applicants). It's really a crapshoot for most. To not get lost in the shuffle is a good way to put it. Even if you have stellar academics, awesome work experience, and a killer GMAT score, it doesn't mean anything unless you're not somehow "lost" in that shuffle of thousands of applications.
Feel free to ask more questions about b-school admission. You're absolutely right about law school being number-based (as well as medical school). B-school is really another beast. A score of 40 MCAT and a 3.9 GPA will pretty much mean that this person will get accepted to one of the best medical schools in the nation. A 750 GMAT and a 3.9 doesn't automatically translate to a top 10 b-school, simply because there are way too many other variables that play into the b-school application (work experience, letters, essays, to name a few).
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