middle square answer is 11
4 to 8 is 4 and 8 - 10 drops 2 which is half
9 to 5 is 4 and 5 - 3 drops 2 which is half
20 to 14 is 6 so 14 drops 3 which is half
with the last puzzle on the outside you have one number the same and the other one less. 4-3 and 2-2, and on the other side 3-2 and 8-8.
To do same with 41 you could end up with 40 - 4 -4 and 1-0 or 4-3 and 1 -1 which would be 31. or even 1-1 and 4-3 which is 13. I would go for 13 as this would make 2s 1s and 8s all different positions.