Find number in the series – 6, 8, 12, 20, 36, ?

Which number replaces the question mark ?

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Answer

Here, as you move down, multiply each number by 2 and subtract 4. It can be obtained by following method:

(6 x 2) – 4 = 8

(8 x 2) – 4 = 12

(12 x 2) – 4 = 20

(20 x 2) – 4 = 36

(36 x 2) – 4 = 68

Correct Answer : 68

(Theo funthingstodo)