The average of $50$ numbers is $38$. If two numbers $45$ and $55$ are discarded,the average of the remaining set of numbers is:

Ten years ago,the average age of $P$ and $Q$ was $20 \text{ years}$. The average age of $P, Q,$ and $R$ is $30 \text{ years}$ now. After $10 \text{ years}$,the age of $R$ will be (in $\text{years}$):

The average age of $20$ boys in the class is $15.6$ years. Five new boys join and the new average becomes $15.56$ years. What is the average age of the five new boys (in years)?

There were $35$ students in a hostel. If the number of students is increased by $7$,the expenditure on food increases by $Rs. \,42$ per day,while the average expenditure per student is reduced by $Rs. \,1$. What was the initial total expenditure on food per day? (in $Rs.$)

The average salary of $20$ workers in an office is $Rs. 1900$ per month. If the manager's salary is added,the average becomes $Rs. 2000$ per month. The manager's annual salary (in $Rs.$) is

The average marks obtained by $40$ students of a class is $86$. If the $5$ highest marks are removed,the average reduces by $1$ mark. The average marks of the top $5$ students is