The average age of a group of 15 employees is 28 years. When 5 more employees join the group, the average age increases by 2 years. The average age of the new employees is?

Question: The average age of a group of 15 employees is 28 years. When 5 more employees join the group, the average age increases by 2 years. The average age of the new employees is?

Solution: Average age of 15 employees = 28 years
Total age of 15 employees = 15 × 28 = 420 years

After 5 more employees join:
Total number of employees = 15 + 5 = 20 employees
New average age = 28 + 2 = 30 years
Total age of 20 employees = 20 × 30 = 600 years

Total age of 5 new employees = 600 - 420 = 180 years

Average age of 5 new employees = 180 ÷ 5 = 36 years