The average salary of $15$ persons is $Rs. 5,500$. If the salary of one person is added,the average increases to $Rs. 5,700$. What is the salary of this one person in $Rs.$?

The average of six numbers is $20$. If one number is removed,the average becomes $15$. What is the number removed?

$5$ members of a team are weighed consecutively and their average weight is calculated after each member is weighed. If the average weight increases by $1 \ kg$ each time,how much heavier is the last player than the first one? (in $kg$)

The average age of a committee of $8$ members is $40 \text{ years}$. $A$ member,aged $55 \text{ years}$,retired and was replaced by a member aged $39 \text{ years}$. The average age of the present committee is (in $\text{years}$):

The sum of three consecutive odd numbers is $38$ more than the average of these numbers. What is the first of these numbers?

The average of marks obtained by $120$ candidates in a certain examination is $35$. If the average marks obtained by passed candidates are $39$ and those of the failed candidates are $15$,then what is the number of candidates who passed the examination?