Question

Three years ago, the average age of a family of five members was 27 years. With the addition of a child into the family, the present average age of the family is still 27 years. Find the present age of the child.
1. 24 years
2. 12 years
3. 16 years
4. 20 years

Answer 1

Correct Answer - Option 2 : 12 years

Given:

Three years ago the age of the family = 27 years

Formula use:

Average of the ages = (Total age/number of members)

Calculations:

⇒ Three years ago the total age of all the family members = 27 × 5 years

⇒ Three years ago the total age of all the family members = 135 years

⇒ After three years total age of the family members = 135 + 3 × 5 years

⇒ After three years total age of the family members = 135 + 15 = 150 years

⇒ The total present age of all the family members = 6 × 27 years

⇒ The total present age of all the family members = 162 years

⇒ The present age of the child = 162 - 150 years

⇒ The present age of the child = 12 years

∴ The present age of the child is 12 years.