The total marks you will get will be the best of 5. That means out off 6 subjects, the best marks you will get in 5 subjects will be accounted for total. So yeah! If you get the lowest marks in Mathematics compared to your other 5 subjects then it will slogged out of the total and the total will be made based on the best 5 subjects.

I hope this might help. All the very best for your future endeavors!