Find out the wrong number from the following number series ?

Question

484, 240, 120, 57, 26.5, 11.25, 3.625

[A] 240

[B] 120

[C] 26.5

[D] 11.25

Answer & Explanation
Option: [B]

The wrong number from the given series is 120. It is replaced by 118

484 x 0.5 - 2 = 240

240 x 0.5 - 2 = 118

118 x 0.5 - 2 = 57

and so on.....