Which number replaces the Question mark - 3,9,17,27,??

Question

Which number replaces the question mark - 12, 9, 7, 3, 4, 6, ??

Answer 1

Answer can be 39
As difference is varying ,
6,8,10 so next will be 12
So 27 + 12 = 39

Answer 2

3,9,17,27, 39, 53, 69

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Answer 3

ANSWER IS 39..

DIFFERENCE IS 6 8 10 12