Answer 9 questions correctly, with a maximum of 36 points. If you make a mistake, 35 points will be deducted. So there will be no 37, 38, 39. Answer 8 questions correctly, with a maximum of 32 points. 2 questions wrong, 30 points. So there won't be 33, 34. Answer 7 questions correctly, with a maximum of 28 points. Wrong 3 questions, 25 points. So there won't be 29 people who answer 6 questions correctly, score 24 points, answer 5 questions correctly and score 20 points.

By analogy, scores can be linked. There are 6 numbers between-10-40 that cannot be obtained, ∴ n = 5 1-6 = 45.

So the answer is: 45.