That is a personal evaluation and depends on the understanding of those subjects by the individual.
I have many students that come in fresh from high school who do not have even a basic grasp on math. Math that seems easy to me and I'm not a math whiz by any stretch.
There are many other more highly advanced subjects that will be much harder than the basics of math, reading, and writing.
If this is something you want then you should go meet with the instructor and let them give you an assessment, if your education is deficient you can decide whether you want to drop your desire or seek remedial education.
Sent from my XT1565 using Tapatalk