What is the next number in this sequence: 2, 6, 12, 20, 30, 42, ?
56
The differences between consecutive terms are 4, 6, 8, 10, 12, increasing by 2 each time. The next difference is 14, so 42 + 14 = 56 (or n(n+1) for n=1,2,3...).
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: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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