+1 to @Fineman. Although my son is not a math major (he’s CS) and didn’t have the math background of many of his classmates, he made good friends in Math 230 that have lasted well beyond the class. As always, Yale students are more collaborative than selfish with psets. Fwiw, he wouldn’t ordinarily be proud of a B+, but he said that he spent as many hours on 230 as the rest of his classes combined, he wasn’t far from an A, and he is convinced that it was well worth it.
For that other university you’re interested in, Math 55 might be a bit tougher.