Question

The average monthly salary of $20$ workers in an office is $Rs.7650$. If the manager's salary is added, the average salary becomes $Rs.8200$ per month. What is the manager's salary per month?

Answer 1

Average monthly salary of $20$ workers $=Rs7650$
Sum of the monthly salaries of $20$ workers $=Rs7650\times 20$ $=Rs153000$

By adding the manager's monthly salary, we get:
Average salary$=Rs.8200$

Now,
Let the manager's monthly salary be $Rsx$.
Thus, we have:
Sum of the monthly salaries of 20 workers + manager $=8200\times 21$

⇒ $153000+x=8200\times 21$

⇒ $153000+x=172200$

⇒ $x=19200$
Therefore, the manager's monthly salary is $Rs19200.$