The average salary of 15 persons is Rs. 5500. If the salary of one person is added, the average increases to Rs. 5700. What is the salary of this one person?
Answer: A
Total salary of 15 persons = 15 × 5500 = 82500.
Total salary of 16 persons = 16 × 5700 = 91200.
Salary of the new person = 91200 - 82500 = 8700.
Alternatively, the new person must bring his own average (5700) plus enough to raise the average of the other 15 people by 200 each. Salary = 5700 + 15 * 200 = 5700 + 3000 = 8700.