Sixth Grade Challenge Curriculum

Answer is 14. Whenever you find a sequence like 0,4,5,11 with hardly any relation between adjacent numbers, it is a wiser to try adding and subtracting small numbers like 1 or 2 to all numbers. Now, alternatively adding 1 and subtracting 1 from each number of the sequence we get 1,3,6,10. This sequence has got a pattern!!!. ................
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