SOLUTION: What are the next two terms in this sequence? 15, 30, 20, 27, 25, 24, 30, 21, 35, 18, ___, ___

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Question 234492: What are the next two terms in this sequence?
15, 30, 20, 27, 25, 24, 30, 21, 35, 18, ___, ___
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
This sequence requires a 2 level solution.
15, 30, 20, 27, 25, 24, 30, 21, 35, 18, 6, 15 First find the difference.
+15, -10, +7, -2, -1, +6, -9, -14,-17, Now find another level of differences.
????+5, -3, +5, -3, +5, -3, +5, -3, +5, -3,
Calculate the first missing number:
-17+5=-12+18=6 ans.
Calculate the next number:
18-6=12-3=9+6=15 ans.