Answer :
the only complete pattern is the middle one
we see that 38-29=9
so the middle number minus the first number equals the third number
for the last row
21-1=20 so you have 1 21 20
for the first one
17- ?=37
54-17=37 54 17 37
we see that 38-29=9
so the middle number minus the first number equals the third number
for the last row
21-1=20 so you have 1 21 20
for the first one
17- ?=37
54-17=37 54 17 37