Look at the sequence: 2, 6, 12, 20, 30, __. What is the next number in this sequence based on a consistent mathematical rule?
42
The differences between consecutive numbers are +4, +6, +8, +10. The next increment must be +12, making 30 + 12 = 42. (Alternatively, the nth term is n*(n+1), so 6*7 = 42).
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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