Multiple choice

In a class there are 41 students, whose average age is 16 years. What will be the average age of the class after three months when two students of age 17 years and 19 years exclude the class and a student of age 20 years joins the class?

  1. Less than 16 years

  2. 16 years

  3. More than 16 years and less than 20 years

  4. 20 years

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Initial total age = 41 × 16 = 656. After 3 months, if no one left/joined: (656 + 41×3)/41 = 17 years. But two students leave (17+19 = 36) and one joins (20), so net change = -16. New total = 656 + 123 - 16 = 763. New avg = 763/40 = 19.075 years, which is between 16 and 20.