In a class of $10$ girls and $20$ boys,Jaya's rank is $4$ among the girls and $18$ in the class. What is Jaya's rank among the boys in the class?

In a class of $20$ students, Alisha's rank is $15^{th}$ from the top. Manav is $4$ ranks above Alisha. What is Manav's rank from the bottom (in $^{th}$)?

In the following number sequence,how many such even numbers are there which are exactly divisible by its immediate preceding number but not exactly divisible by its immediate following number?
$3, 8, 4, 1, 5, 7, 2, 8, 3, 4, 8, 9, 3, 9, 4, 2, 1, 5, 8, 2$

In a class of $40$ students,Samir's rank from the top is $12^{th}$. Alok is $8$ ranks below Samir. What is Alok's rank from the bottom?

Saiyeev ranks seventh from the top and twenty-eighth from the bottom in a class. How many students are there in the class?

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