@Chumly,
If that's the case, I think it's your responsibility to know what prerequisites they have to meet your class requirements. You can't expect students to study quantitative analysis without understanding basic math concepts.
If your course material is basic, then you have a case. Otherwise, it seems your course material is too difficult for this level of students. What are their grade point average in all other subjects? That will provide a clue as to whether they are lax, lazy, or unprepared.