Observe the differences between consecutive terms:
6 - 2 = 4
12 - 6 = 6
20 - 12 = 8
30 - 20 = 10
Differences are: 4, 6, 8, 10 — increasing by 2 each time.
The next difference should be: 10 + 2 = 12
So, next term = last term + next difference = 30 + 12 = 42
Answer: 42