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Verbal Reasoning · Q106

Series Completion

Competitive Exams · Verbal Reasoning · question 106

Q106

One term in the number series is wrong. Find out the wrong term. 3, 7, 15, 39, 63, 127, 255, 511

A.
15
B.
39
Answer
C.
63
D.
127

Answer: Option B

Solution

Answer: Option B
Solution:
The correct pattern is x 2 + 1.
So, 39 is wrong and must be replaced by (15 x 2 + 1) i.e. 31.