# Difficult Averages Solved QuestionAptitude Discussion

 Q. The average monthly salary of 12 workers and 3 managers in a factory was Rs. 600. When one of the manager whose salary was Rs. 720, was replaced with a new manager, then the average salary of the team went down to 580. What is the salary of the new manager?
 ✖ A. 570 ✔ B. 420 ✖ C. 690 ✖ D. 640

Solution:
Option(B) is correct

The total salary amount = $15 \times 600 = 9000$

The salary of the exiting manager = 720.

Therefore, the salary of 12 workers and the remaining 2 managers:

$=9000−720=8280$

When a new manager joins, the new average salary drops to Rs.580 for the total team of 15 of them.

The total salary for the 15 people i.e., 12 workers, 2 old managers and 1 new manager = $580\times 15=8700$

Therefore, the salary of the new manager is $9000-8700 = 300$ less than that of the old manager who left the company, which is equal to $720-300 = 420$.

Another alternate method of doing the problem is as follows:

The average salary dropped by Rs.20 for 15 of them. Therefore, the overall salary has dropped by $15\times 20=300$.

Therefore, the new manager's salary should be Rs.300 less than that of the old manager =$720−300$=420.

## (4) Comment(s)

Sri Devi
()

1) (12w+3.720)/15=600

...... avg salary of 12 workers and 3 managers (=15 employees)

w=570 i.e., salary of one worker is calculated :)

2) ((12*570)+(2*720)+x)/15 = 580

here, x is the salary of the new joinee and equals 420 :)

Sri Devi
()

1) (12w+3.720)/15=600

...... avg salary of 12 workers and 3 managers (=15 employees)

w=570 i.e., salary of one worker is calculated :)

2) ((12*570)+(2*720)+x)/15 = 580

here, x is the salary of the new joinee :)

Paramjot
()

""Therefore, the salary of 12 workers and the remaining 2 managers:

=9000−720=8280""

This part is Useless. No need to calculate.

Naveen
()

The solution can be given in a brief manner: The total salary of 15 employees before the manager left:

$= 600 \times 15 = 9000$

Total salary of 15 employees after the new manager joined $= 8700$

The difference between old manager's and new manager's salary $= 300$

so the new managers salary:

$= 720 -300$

$=\textbf{420}$