which number replaces the question mark?

which number replaces the question mark puzzle

30

Explanation:
As you can see the lower number rows are always bigger than upper row ones with the difference going up by 3 with every step

34 - 32 = 2
32 - 27 = 5 (difference going up by 3 from last difference)
56 - 48 = 8 (difference going up by 3 from last difference)
? - 19 = 11 (difference going up by 3 from last difference)
so ? = 30