Incoming Cal Freshman multi-majoring questions.

I will be an incoming freshman at Cal this year and I really want to quadruple major. I want to major in Applied Math (with a cluster in physics), Computer Science, Economics, and Statistics. Can someone give me an overview of what classes I have to take. Specifically on what the two overlapping classes in multi majoring mean. I don’t quite understand the concept of that. Also I have already fulfilled math 1a and math 1b. Also, if I take math 53 and math 54, they do count for all four of the majors as a lower division course, right?

You can overlap all of the lower division courses between majors that you want, but only two upper division courses can overlap across any two of your majors. So you cannot (officially) double major in (for example) pure math and applied math, which have four of the same upper division courses required for both. Most L&S majors require 8 upper division courses, so you would typically need 14 upper division courses for two majors, 20 for three majors, and 26 for four majors. Since normal course loads of 4 courses per semester mean a total of 32 courses in 8 semesters, that is a lot to squeeze in; remember that there are other requirements like breadth requirements, reading and composition, etc…

It is more realistic to choose one as your primary major, and take electives of interest in the other subjects. What are your academic and professional goals?

For those majors, consider the following courses this semester:

applied math: Math 53, 54, 55 (or CS 70 if you also major in CS); Physics 7A (if you want to apply math to physics)
computer science: Math 54; CS 61A, 70.
economics: Math 53, 54 (assuming that you are interested in the math-heavy version with Economics 101A, 101B, and 141); Economics 1
statistics: Math 53, 54
L&S requirements: reading and composition courses, courses in 7-course breadth categories not satisfied by your majors of interest, including American Cultures courses

Note: honors courses are available for math and physics courses (prefix H, as in Math H53, H54; Physics H7A).