Question

What are the next three terms in the sequence?

Answer 1

-1 + 10 = 9 +10 = 19 + 10 = 29 so the next would be 39 because you add ten to it and there is only one answer with 39 so it's C

Answer 2

In this sequence it looks as each number is increasing by 10

-1 
+10
9
+10
19
+10
29

And so on.

So following this pattern it looks as if the answer is 
C : 39, 49, 59

Hope this helps!
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