Sample solution:

(this is only a sample; there are many other ways to write some of these formulas)

F14: = F8+F9+F10+F11+F12+F13
      or more simply =SUM(F8:F13)
      although we didn't really talk about that, so more students wrote the above
C12: = B8/C8*25 + B9/C9*25
C13: = F14/6
      (no penalty for miscounting and putting /5 or /7)
C14: = C12+C13
C15: = IF(B10/C10 > C14/60, B10/C10*100, C14 + B10/C10*40)

More on C15:

The most obvious way to write it:
= IF(B10/C10 > C14/60, B10/C10*100, C14 + B10/C10*40)
But note that this is the same question as whether the exam grade is greater than the complete final grade as calculated with the term work.
In other words,
= IF(B10/C10*100 > C14 + B10/C10*40, B10/C10*100, C14 + B10/C10*40)
This then can be simplified to:
=MAX(B10/C10*100, C14 + B10/C10*40)
(The first version was accepted for full marks.)
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