Look at this sequence: 2, 6, 12, 20, 30, ?. What is the next number in the pattern?
42
The differences between consecutive terms are increasing by 2: (+4, +6, +8, +10). The next difference is +12. 30 + 12 = 42. (Alternatively, n(n+1) for n=1,2,3,4,5,6 gives 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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