Question
In a group of 28 friends, the average age is 22 years.
One person aged 20 leaves, and 2 new people with an average age of 24 years join. When a new member’s age is also included, the average age becomes 23 years. What is the age of the new member?Solution
Initial total age = 28 × 22 = 616 years
Age of 2 new members = 2 × 24 = 48 years Let the new member’s age be ‘y’ years.
New total age = 616 - 20 + 48 + y = (644 + y) years
New total number of people = 28 - 1 + 2 + 1 = 30
New total age = 30 × 23 = 690 years
So, age of the new member = 690 - 644 = 46 years
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