What is the next number in this logical sequence: 2, 6, 12, 20, 30, ___?
42
The differences between consecutive terms increase by 2 each time: +4, +6, +8, +10. The next difference is +12, so 30 + 12 = 42. (Alternatively, n × (n + 1): 1×2, 2×3, 3×4, 4×5, 5×6, 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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