Test Index

SSC CPO SI and ASI Model Paper 9

Directions (Q. 7–8): In each of the following number series, one number is incorrect. Find out the incorrect number.

Question : 8 of 200

Marks: +1, -0

4, 8, 16, 30, 64, 128, 256

Solution:

Concept:

The series follows a doubling pattern, so each term should be twice the previous term.

Explanation:

Check the pattern:

4 \times 2 = 8

and

8 \times 2 = 16

The next term should be

16 \times 2 = 32

, but the series gives

30

After that,

32 \times 2 = 64

64 \times 2 = 128

, and

128 \times 2 = 256

, which match the rest of the series.

So,

30

is the incorrect term and should be replaced by

32

Answer:

The incorrect number is

30

Go to Question:

Prev Question

Next Question