Question

The average age of 18 students in a class is 22 years. If 12 more boys joined the class, the average of the whole class is increased by 2 years. What is the average age of the 12 new students?

1. 14 year
2. 27 year
3. 35 year
4. 36 year

Answer 1

Correct Answer - Option 2 : 27 year

Given:

The average age of 18 students in a class = 22 years

Concept:

Average value = Sum of all values/Number of values

Calculation:

Let, the average age of the 12 new students = x years

According to the question,

⇒ 18 × 22 + 12 × x = (18 + 12) × (22 + 2)

⇒ 396 + 12x = 720

⇒ 12x = 324

⇒ x = 27

∴ Average age of the 12 new students = 27 years