1, 2, 3, 6, 9, 18, , 54 - Number Series - Series Completion - Verbal Reasoning question

In following question, a number series is given with one term missing. Choose the correct alternative that will same pattern and fill in the blank spaces. - 1, 2, 3, 6, 9, 18, , 54

A. 18

B. 27

C. 36

D. 81

E. None of the above

Answer: B. 27

The numbers are alternately multiplied by 2 and 3 / 2.
Thus, 1 * 2 = 2,
2 * 3 / 2 = 3,
3 * 2 = 6,
6 * 3 / 2 = 9 and so on.
.'. Missing number = 18 * 3 / 2 = 27.

Posted in: Number Series - Series Completion - Verbal Reasoning