What is the next number in the following sequence: 2, 6, 12, 20, 30, ___?
42
The differences between consecutive terms increase by 2 each time (+4, +6, +8, +10, +12). 30 + 12 = 42. Alternatively, the n-th term is n * (n + 1), so 6 * 7 = 42.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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