Major Prep Grades

Hi! How badly will major prep grade affect in my admission to UC’s, specifically UCSD and UCLA since they play so much emphasis on gpa and major prep grades. I am currently an economics/mathematics joint major and I’m probably to receive a B in CALC 3 by the end of the semester which is a major prep course for both UC’s.

That sounds like your only B in a major prep course. I wouldn’t worry about it, meaning if you don’t get in it isn’t likely due to the B.