missing number is 9 column1+column2= column4 5+2=7 6+3=9 4+1=5 8+1=9

Find the missing number in the following grid?

Find the missing number ?

6, 2, 17, 1, 4, 11, 3, 7, ?

Find the missing no in the following grid -

2 8 9 3 2 4 3 6 ?