Find out the incorrect number 1, 3, 7, 15, 27, 63, 127 - Number Series - Series Completion - Verba

A. 7

B. 15

C. 27

D. 63

E. None of the above

Answer: C. 27

The sequence is + 2, + 4, + 8,.... i.e. + 2, + 2², + 2³,....
So, 27 is wrong and must be replaced by (15 + 2⁴) i.e. (15 +16) or 31.

Posted in: Number Series - Series Completion - Verbal Reasoning