The average monthly salary of 20 employees in an organisation is Rs. 1400. If the manager's salary is added, then the average salary increases by Rs. 100. What is the manager's monthly salary ?  Pick
A) 3600	B) 3890	C) 88798	D) 2789	E) 3500
Explanation:   Manager's monthly salary Rs. (1500 * 21 - 1400 * 20) = Rs. 3500.   Answer: 3500
<result>E</result>
The average monthly salary of 20 employees in an organisation is Rs. 1400. If the manager's salary is added, then the average salary increases by Rs. 100. What is the manager's monthly salary ?