In a row of children facing North,Ritesh is $12^{th}$ from the left end. Sudhir,who is $22^{nd}$ from the right end,is $4^{th}$ to the right of Ritesh. How many children are there in the row in total?

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?

In a row of girls, if Savitha who is tenth from the left and Anita who is ninth from the right interchange their places, Savitha becomes fifteenth from the left. How many girls are there in the row?

If the third day of a month is Monday,which of the following will be the fifth day from $21^{st}$ of the month?

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

How many numbers between $9$ and $54$ (inclusive) are exactly divisible by $9$ but not by $3$?