There's really no way of knowing whether X amount of time will be enough. There is no magic timeline or target number of hours that you can hit to guarantee your success. It depends a lot on who you are, how you study (your personal methods and the review materials you're using), when you study, and your background with the subject matter going into it. For some people, 10 weeks isn't enough to pass. For others, 3 weeks might be sufficient to master the material.
Personally, I'm addicted to cramming and usually didn't start to study until a week before the scheduled exam date and then I took a couple days PTO from my full-time public accounting job right before and then passed with flying colors. I'm an example of everything people tell you NOT to do, but it works for me… I'm not saying that 5 weeks is or isn't enough time, and I'm definitely not telling you to cram. What I'm saying is basically “know thyself.” I knew before I ever took my first exam that I was a crammer and I don't have the patience or attention span for several weeks of short bursts of studying. I crammed my whole way through high school when they told me not to, and then I crammed my way through college when they said I wouldn't be able to anymore, so when it came to the CPA exam, I knew I could cram my way through that too.
How did you pass exams in college? What worked for you then? Odds are you haven't changed that much and the same things you did then will work now. Don't psych yourself out too much, it's really just 4 college-level-difficulty exams.
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