In a row of $21$ girls, when Anita was shifted by four places towards the right, she became $12^{th}$ from the left end. What was her earlier position from the right end of the row (in $^{th}$)?

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

How many numbers from $1$ to $100$ are there,each of which is not only exactly divisible by $4$ but also has $4$ as a digit?

In a row of boys,Deepak is seventh from the left and Madhu is twelfth from the right. If they interchange their positions,Deepak becomes twenty-second from the left. How many boys are there in the row?

Akshay is $16^{th}$ from the left end in a row of boys and Vijay is $18^{th}$ from the right end. Avinash is $11^{th}$ from Akshay towards the right end and $3^{rd}$ from Vijay towards the right end. How many boys are there in the row?

In the following series of numbers,find out how many times $1, 3$ and $7$ have appeared together,with $7$ being in the middle and $1$ and $3$ on either side of $7$?
$2, 9, 7, 3, 1, 7, 3, 7, 7, 1, 3, 3, 1, 7, 3, 8, 5, 7, 1, 3, 7, 7, 1, 7, 3, 9, 0, 6$