I have an Excel-sheet with student grades, ranging from 0 to 5. If a student didn't submit a solution for the test he/she gets a score of 'NA'.
My sheet looks like the following:
|student||test 1||test 2||test 3||test 4||test 5||average|
My question is: how can I replace the 'NA' by a score of 0 but only in the formula for calculating the average (so not the cell-contents)?
Thank you in advance!