AND IF OR rule

Hi,

I am doing my coursework and ive got to this point where i cannot get past this problem.

1. A small file of student records for 26 students is given at the end of this document. The format of each record in the file is: Name, Coursework 1 mark, Coursework 2 mark, Coursework 3 mark, Part 1 Exam mark, Part 2 Exam mark. All of these numbers represent percentages.
2. Load the student records into a spreadsheet by first saving them into a text file (copy and paste it into Notepad, and then Open that file within Excel).
3. Add a column called CW Average giving the student's overall coursework average.
4. The contribution of each of the five marks in each student record to the overall course average is: Coursework 1(10%), Coursework 2(10%), Coursework 3(20%), Part 1(20%), Part 2 (40%). Add a column called Total giving the students' overall course average.
5. A student cannot pass CSC6001 if they achieve an average of less than 35% for the coursework. Add a column that shows the Returned Mark for the course. Provided that the student has achieved a coursework average of 35% or more, then the Returned Mark is simply the student's overall course average. However, if they do not average 35% for the coursework, then the maximum returned mark is 35%. In this case, if their overall course average is more than 35%, then the Returned Mark is 35%.
6. Add a column called Class that displays the equivalent Honours degree classification for each student's Returned Mark (i.e. F, III, 2.II, 2.I, 1)
7. Produce a chart showing the number of students in each degree class. Place the chart on an appropriately named worksheet.
8. Add a row giving the average for each of the numeric columns.

My problem is number 5. I cannot get it to recognize %'ages so i cannot use =if(E2.... and so on..can some one help me how do i interpret number 5 in a rule.

Thanks.