Ravi is $7$ ranks ahead of Sumit in a class of $39$ students. If Sumit's rank is $17^{th}$ from the last, what is Ravi's rank from the start (in $^{th}$)?

If $16 \times 85 = 8651$,what is $73 \times 42$?

Five men $A, B, C, D$ and $E$ read a newspaper. The one who reads first gives it to $C$. The one who reads last had taken it from $A$. $E$ was not the first or the last to read. There were two readers between $B$ and $A$. To whom did $B$ pass the newspaper?

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?

How many $7$'s are there in the following series which are preceded by $6$ but not preceded by $8$ (i.e.,the sequence $6, 7$ where $6$ is not immediately preceded by $8$)?
Series: $8, 7, 6, 7, 8, 6, 7, 5, 6, 7, 9, 7, 6, 1, 6, 7, 7, 6, 8, 8, 6, 9, 7, 6, 8, 7$

$L, M, N$ and $P$ are sitting around a circle and facing the centre. $P$ is to the immediate left of $N$. $L$ is between $N$ and $M$. What is the position of $M$?