What approximate value

251, 130, 274, ?, 301, 76 

14, 17, 23, 32, ?, 59

18, 30, 54, 90, 138, ?

What will come in place of the question mark (?) in the following series?

18, 22, 34, 70, 178, ?

7      4      5      9      20       ?       160.5

4, 4, 12, 60, ?, 3780

12, 14, 20, 32, ?, 82 

What will come in place of the question mark (?) in the following series?

45, 68, 114, 183, 275, ?

What will come in place of the question mark (?) in the following number series?

21, 42, 67, 96, ?, 166

What will come in place of the question mark (?) in the following series?

4, 2605, 5309, 8118, ?