How many $8$s are there in the following number sequence which are preceded by $7$ but not immediately followed by $4$?
$2, 3, 8, 2, 5, 7, 8, 3, 7, 8, 4, 6, 9, 8, 4, 3, 2, 7, 8, 9, 5, 7, 8, 1, 5, 2, 9$

Three persons $A, B$ and $C$ are standing in a queue. There are $5$ persons between $A$ and $B$ and $8$ persons between $B$ and $C$. If there are $3$ persons ahead of $C$ and $21$ persons behind $A$, what could be the minimum number of persons in the queue?

How many $7$s are there in the following series which are immediately preceded by $6$ but not immediately followed by $4$?
$7, 4, 2, 7, 8, 4, 3, 6, 7, 5, 3, 5, 7, 8, 4, 3, 7, 6, 7, 2, 4, 0, 6, 7, 4, 3$

In a queue of children,Kashish is fifth from the left and Mona is sixth from the right. When they interchange their places among themselves,Kashish becomes thirteenth from the left. Now what will be Mona's position from the right (in $^{th}$)?

Abhishek ranks thirteenth in a class of thirty-one students. What is his rank from the last (in $19^{th}$)?

$5, 1, 4, 7, 3, 9, 8, 5, 7, 2, 6, 3, 1, 5, 8, 6, 3, 8, 5, 2, 2, 4, 3, 4, 9, 6$
How many odd numbers are there in the sequence which are immediately followed by an odd number?