Stop going "i can't do this" and think: you have to output an average, and you know what an average is:
average = Sum of items / number of items
For example: the average of the first five non zero integers is:
av = (1 + 2 + 3 + 4 + 5) / 5
So read your instructions and think about what your tutor expects.
(Then read them again and think about what you have written already!)