I went to college in the USA, and I understand that undergrads are often put into classes far outside of their expertise. Still, I expect college students to be able to count to 6 and understand fractions. Even the remedial algebra students I helped in high school weren't that bad.
CS major in first year who has been interested in math and science as a kid? Probably not.
First year college in the USA is very broad. It’s not like university in Europe / UK where you specialize in one subject only for your bachelors.