Question

__5______ 9______ 12
4 16 2___ 8 12 2 ___11 ? 6
__1_______ 5______ 3​

Underscore is just for spacing purpose. They are 3 different examples of some logic, find out missing number.​

Answer 1

$5 + 4 = 9 + 3 = 12 \\ 4 + 12 = 16 - 14 = 2 + 6 = 8 \\ 1 + 4 = 5 - 2 = 3$