Q. What should come in place of question mark (?) in the following number series?
11   14   19    28    43    ?

Explanation:

In this question, the difference between two consecutive number is basically odd number starting from 3 and there is a skip of numbers as soon as we move towards the end of the series . 

In first gap, 3 
In second group 5 , skip 0
In third gap 9, skip 1----- that is 7
In fourth gap 15 ,skip 2 ---11,13
Similarly 
In fifth gap skip 3 -----17,19,21
So the number will be 23 + previous number

23+43 = 66