yeah, like narue said you just have to have arithmetic skills.
if you don't know the answer to 3+5, then fuck you.
but i'm sure you do know. asm will probably test your math the least of all languages...until you try to get clever, then you're dealing with bits and shit.
most CS majors only have you take 5 or 6 upper-level math courses.
it's NOT that hard...and if it is?...
try something else.
good luck!